Trial Outcomes & Findings for Gabapentin and Risk of Pancreatic Cancer and Renal Cancer (GPRD) (NCT NCT01138124)

NCT ID: NCT01138124

Last Updated: 2017-05-30

Results Overview

Incident pancreatic cancer. Gabapentin Exposure Description: Without 2 year lag = Gabapentin prescription from cohort entry to index date. With 2 year lag = Gabapentin prescription from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer).

Recruitment status

COMPLETED

Target enrollment

54202 participants

Primary outcome timeframe

The case index date (ID) was the date of incident pancreatic cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control ID was the date at which the follow-up time from his/her cohort entry was the same as that for the case

Results posted on

2017-05-30

Participant Flow

Patients were not recruited for nor enrolled in this study. This study is a retrospective observational study. Data from medical records or insurance claims databases are anonymized and used to develop a patient cohort. All diagnoses and treatment are recorded in the course of routine medical practice.

Actual number of patients may be less, as it is possible for a patient to be represented in more than one of the four arms (See "Participant Flow: Overall Study" Table) because of the risk set sampling.

Participant milestones

Participant milestones
Measure
Pancreatic Cancer Cases
Incident pancreatic cancer, defined as first time pancreatic cancer diagnosis (READ/ Oxford Medical Information System \[OXMIS\] codes) in the General Practice Research Database (GPRD) study cohort. Entry into the GPRD study cohort began Jan 1, 1993, or at the time of GPRD registration if after Jan 1, 1993. Subjects were required to have at least 2 years of follow-up prior to the index date. The index date for cases was the date of incident pancreatic cancer diagnosis. Exocrine pancreatic cancer, endocrine pancreatic cancer, and carcinoma in situ were included. Cancer metastatic to the pancreas was excluded.
Pancreatic Cancer Controls
Pancreatic cancer cases were risk set matched with up to 10 controls for sex, age at GPRD study cohort entry (within two years), calendar year of cohort entry (within one year), and General Practice site. The index date for controls was set as the date at which the follow-up time from cohort entry was the same as the case. The index date was chosen so as to give the control equal follow-up time to that of the case for ascertainment of use of gabapentin.
Renal Cancer Cases
Incident renal cancer, defined as first time renal cancer diagnosis (READ/OXMIS codes) in the GPRD study cohort. Entry into the GPRD study cohort began Jan 1, 1993, or at the time of GPRD registration if after Jan 1, 1993. Subjects were required to have at least 2 years of follow-up prior to the index date. The index date for cases was the date of incident renal cancer diagnosis. Renal cell carcinoma and renal pelvis cancer were included; Wilm's tumor and cancer metastatic to kidney were excluded.
Renal Cancer Controls
Renal cancer cases were risk set matched with up to 10 controls for sex, age at cohort entry (within two years), calendar year of cohort entry (within one year), and General Practice site. The index date for controls was set as the date at which the follow-up time from cohort entry was the same as the case. The index date was chosen so as to give the control equal follow-up time to that of the case for ascertainment of use of gabapentin.
Overall Study
STARTED
3149
30026
1981
19046
Overall Study
COMPLETED
3149
30026
1981
19046
Overall Study
NOT COMPLETED
0
0
0
0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Gabapentin and Risk of Pancreatic Cancer and Renal Cancer (GPRD)

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Pancreatic Cancer Cases
n=3149 Participants
Incident pancreatic cancer, defined as first time pancreatic cancer diagnosis (READ/OXMIS codes) in the GPRD study cohort. Entry into the GPRD study cohort began Jan 1, 1993, or at the time of GPRD registration if after Jan 1, 1993. Subjects were required to have at least 2 years of follow-up prior to the index date. The index date for cases was the date of incident pancreatic cancer diagnosis. Exocrine pancreatic cancer, endocrine pancreatic cancer, and carcinoma in situ were included. Cancer metastatic to the pancreas was excluded.
Pancreatic Cancer Controls
n=30026 Participants
Pancreatic cancer cases were risk set matched with up to 10 controls for sex, age at cohort entry (within two years), calendar year of cohort entry (within one year), and General Practice site. The index date for controls was set as the date at which the follow-up time from cohort entry was the same as the case. The index date was chosen so as to give the control equal follow-up time to that of the case for ascertainment of use of gabapentin.
Renal Cancer Cases
n=1981 Participants
Incident renal cancer, defined as first time renal cancer diagnosis (READ/OXMIS codes) in the GPRD study cohort. Entry into the GPRD study cohort began Jan 1, 1993, or at the time of GPRD registration if after Jan 1, 1993. Subjects were required to have at least 2 years of follow-up prior to the index date. The index date for cases was the date of incident renal cancer diagnosis. Renal cell carcinoma and renal pelvis cancer were included; Wilm's tumor and cancer metastatic to kidney were excluded.
Renal Cancer Controls
n=19046 Participants
Renal cancer cases were risk set matched with up to 10 controls for sex, age at cohort entry (within two years), calendar year of cohort entry (within one year), and General Practice site. The index date for controls was set as the date at which the follow-up time from cohort entry was the same as the case. The index date was chosen so as to give the control equal follow-up time to that of the case for ascertainment of use of gabapentin.
Total
n=54202 Participants
Total of all reporting groups
Age, Customized
<40 years
18 Participants
n=99 Participants
199 Participants
n=107 Participants
43 Participants
n=206 Participants
446 Participants
n=7 Participants
706 Participants
n=31 Participants
Age, Customized
40-49 years
86 Participants
n=99 Participants
897 Participants
n=107 Participants
134 Participants
n=206 Participants
1348 Participants
n=7 Participants
2465 Participants
n=31 Participants
Age, Customized
50-59 years
367 Participants
n=99 Participants
3616 Participants
n=107 Participants
355 Participants
n=206 Participants
3418 Participants
n=7 Participants
7756 Participants
n=31 Participants
Age, Customized
60-69 years
748 Participants
n=99 Participants
7234 Participants
n=107 Participants
528 Participants
n=206 Participants
5199 Participants
n=7 Participants
13709 Participants
n=31 Participants
Age, Customized
70-79 years
1033 Participants
n=99 Participants
10092 Participants
n=107 Participants
594 Participants
n=206 Participants
5604 Participants
n=7 Participants
17323 Participants
n=31 Participants
Age, Customized
>=80 years
897 Participants
n=99 Participants
7988 Participants
n=107 Participants
327 Participants
n=206 Participants
3031 Participants
n=7 Participants
12243 Participants
n=31 Participants
Sex: Female, Male
Female
1603 Participants
n=99 Participants
15316 Participants
n=107 Participants
759 Participants
n=206 Participants
7273 Participants
n=7 Participants
24951 Participants
n=31 Participants
Sex: Female, Male
Male
1546 Participants
n=99 Participants
14710 Participants
n=107 Participants
1222 Participants
n=206 Participants
11773 Participants
n=7 Participants
29251 Participants
n=31 Participants
Number of participants with the indicated duration of follow-up from GPRD registration to index date
2-3 years
173 participants
n=99 Participants
1460 participants
n=107 Participants
129 participants
n=206 Participants
1081 participants
n=7 Participants
2843 participants
n=31 Participants
Number of participants with the indicated duration of follow-up from GPRD registration to index date
4-5 years
185 participants
n=99 Participants
1509 participants
n=107 Participants
117 participants
n=206 Participants
1135 participants
n=7 Participants
2946 participants
n=31 Participants
Number of participants with the indicated duration of follow-up from GPRD registration to index date
6-7 years
237 participants
n=99 Participants
2007 participants
n=107 Participants
141 participants
n=206 Participants
1280 participants
n=7 Participants
3665 participants
n=31 Participants
Number of participants with the indicated duration of follow-up from GPRD registration to index date
>=8 years
2554 participants
n=99 Participants
25050 participants
n=107 Participants
1594 participants
n=206 Participants
15550 participants
n=7 Participants
44748 participants
n=31 Participants
Number of participants with the indicated duration of follow-up from GPRD study cohort entry to ID
2-3 years
446 participants
n=99 Participants
4121 participants
n=107 Participants
286 participants
n=206 Participants
2653 participants
n=7 Participants
7506 participants
n=31 Participants
Number of participants with the indicated duration of follow-up from GPRD study cohort entry to ID
4-5 years
396 participants
n=99 Participants
3656 participants
n=107 Participants
226 participants
n=206 Participants
2122 participants
n=7 Participants
6400 participants
n=31 Participants
Number of participants with the indicated duration of follow-up from GPRD study cohort entry to ID
6-7 years
447 participants
n=99 Participants
4213 participants
n=107 Participants
246 participants
n=206 Participants
2338 participants
n=7 Participants
7244 participants
n=31 Participants
Number of participants with the indicated duration of follow-up from GPRD study cohort entry to ID
>=8 years
1860 participants
n=99 Participants
18036 participants
n=107 Participants
1223 participants
n=206 Participants
11933 participants
n=7 Participants
33052 participants
n=31 Participants
Number of participants with the indicated body mass index (BMI)
<18.5 kg/m^2
25 participants
n=99 Participants
203 participants
n=107 Participants
18 participants
n=206 Participants
110 participants
n=7 Participants
356 participants
n=31 Participants
Number of participants with the indicated body mass index (BMI)
18.5 to 24.99 kg/m^2
459 participants
n=99 Participants
3678 participants
n=107 Participants
237 participants
n=206 Participants
2236 participants
n=7 Participants
6610 participants
n=31 Participants
Number of participants with the indicated body mass index (BMI)
25 to 29.99 kg/m^2
457 participants
n=99 Participants
4250 participants
n=107 Participants
326 participants
n=206 Participants
2938 participants
n=7 Participants
7971 participants
n=31 Participants
Number of participants with the indicated body mass index (BMI)
>=30 kg/m^2
291 participants
n=99 Participants
2476 participants
n=107 Participants
250 participants
n=206 Participants
1773 participants
n=7 Participants
4790 participants
n=31 Participants
Number of participants with the indicated body mass index (BMI)
Missing
1917 participants
n=99 Participants
19419 participants
n=107 Participants
1150 participants
n=206 Participants
11989 participants
n=7 Participants
34475 participants
n=31 Participants
Number of participants with the indicated smoking status
Current Smoker
731 participants
n=99 Participants
4857 participants
n=107 Participants
476 participants
n=206 Participants
3555 participants
n=7 Participants
9619 participants
n=31 Participants
Number of participants with the indicated smoking status
Ex-smoker
768 participants
n=99 Participants
6626 participants
n=107 Participants
524 participants
n=206 Participants
4589 participants
n=7 Participants
12507 participants
n=31 Participants
Number of participants with the indicated smoking status
Never Smoked
1385 participants
n=99 Participants
15249 participants
n=107 Participants
867 participants
n=206 Participants
9121 participants
n=7 Participants
26622 participants
n=31 Participants
Number of participants with the indicated smoking status
Status Unknown
265 participants
n=99 Participants
3294 participants
n=107 Participants
114 participants
n=206 Participants
1781 participants
n=7 Participants
5454 participants
n=31 Participants
Number of participants with the indicated medical conditions in Pancreatic Cancer Cases/Controls
Diabetes (>=2 years prior to index date [ID])
363 participants
n=99 Participants
2137 participants
n=107 Participants
0 participants
n=206 Participants
0 participants
n=7 Participants
2500 participants
n=31 Participants
Number of participants with the indicated medical conditions in Pancreatic Cancer Cases/Controls
Epilepsy
53 participants
n=99 Participants
458 participants
n=107 Participants
0 participants
n=206 Participants
0 participants
n=7 Participants
511 participants
n=31 Participants
Number of participants with the indicated medical conditions in Pancreatic Cancer Cases/Controls
Neuropathic Pain
737 participants
n=99 Participants
6616 participants
n=107 Participants
0 participants
n=206 Participants
0 participants
n=7 Participants
7353 participants
n=31 Participants
Number of participants with the indicated medical conditions in Pancreatic Cancer Cases/Controls
Chronic Pancreatitis (>=2 years prior to ID)
13 participants
n=99 Participants
17 participants
n=107 Participants
0 participants
n=206 Participants
0 participants
n=7 Participants
30 participants
n=31 Participants
Number of participants with the indicated medical conditions/drug use in Renal Cancer Cases/Controls
Hypertension
0 participants
n=99 Participants
0 participants
n=107 Participants
1159 participants
n=206 Participants
9113 participants
n=7 Participants
10272 participants
n=31 Participants
Number of participants with the indicated medical conditions/drug use in Renal Cancer Cases/Controls
Diuretic use
0 participants
n=99 Participants
0 participants
n=107 Participants
875 participants
n=206 Participants
6396 participants
n=7 Participants
7271 participants
n=31 Participants
Number of participants with the indicated medical conditions/drug use in Renal Cancer Cases/Controls
Diabetes
0 participants
n=99 Participants
0 participants
n=107 Participants
240 participants
n=206 Participants
1598 participants
n=7 Participants
1838 participants
n=31 Participants
Number of participants with the indicated medical conditions/drug use in Renal Cancer Cases/Controls
Epilepsy
0 participants
n=99 Participants
0 participants
n=107 Participants
33 participants
n=206 Participants
303 participants
n=7 Participants
336 participants
n=31 Participants
Number of participants with the indicated medical conditions/drug use in Renal Cancer Cases/Controls
Neuropathic Pain
0 participants
n=99 Participants
0 participants
n=107 Participants
428 participants
n=206 Participants
4018 participants
n=7 Participants
4446 participants
n=31 Participants

PRIMARY outcome

Timeframe: The case index date (ID) was the date of incident pancreatic cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control ID was the date at which the follow-up time from his/her cohort entry was the same as that for the case

Population: Cases and controls were drawn from the GPRD study cohort. Entry into the study cohort began Jan 1, 1993, or at the time of GPRD registration if after Jan 1, 1993. Follow-up ended Dec 31, 2008, or earlier if the respective cancer was diagnosed or if the participant left the GPRD for any reason including death.

Incident pancreatic cancer. Gabapentin Exposure Description: Without 2 year lag = Gabapentin prescription from cohort entry to index date. With 2 year lag = Gabapentin prescription from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer).

Outcome measures

Outcome measures
Measure
Cases
n=3149 Participants
Cases
Controls
n=30026 Participants
Controls
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin
Ever (without 2 year lag)
56 participants
253 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin
Never (without 2 year lag)
3093 participants
29773 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin
Ever (with 2 year lag)
24 participants
143 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin
Never (with 2 year lag)
3125 participants
29883 participants

PRIMARY outcome

Timeframe: The case index date (ID) was the date of incident pancreatic cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control ID was the date at which the follow-up time from his/her cohort entry was the same as that for the case

Population: Cases and controls were drawn from the GPRD study cohort. Entry into the study cohort began Jan 1, 1993, or at the time of GPRD registration if after Jan 1, 1993. Follow-up ended Dec 31, 2008, or earlier if the respective cancer was diagnosed or if the participant left the GPRD for any reason including death.

Incident pancreatic cancer. Gabapentin Exposure Description: Without 2 year lag = Gabapentin exposure from cohort entry to index date. With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Tertiles without 2 year lag: Tertile 1 (1-2 prescriptions),Tertile 2 (3-8 prescriptions), and Tertile 3 (9-218 prescriptions). Tertile's with 2 year lag: Tertile 1 (1-2 prescriptions), Tertile 2 (3-10 prescriptions),Tertile 3 (11-191 prescriptions).

Outcome measures

Outcome measures
Measure
Cases
n=3149 Participants
Cases
Controls
n=30026 Participants
Controls
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions
Never (without 2 year lag)
3093 participants
29773 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions
Tertile 1 (without 2 year lag)
30 participants
99 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions
Tertile 2 (without 2 year lag)
12 participants
64 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions
Tertile 3 (without 2 year lag)
14 participants
90 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions
Never (with 2 year lag)
3125 participants
29883 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions
Tertile 1 (with 2 year lag)
14 participants
48 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions
Tertile 2 (with 2 year lag)
3 participants
49 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions
Tertile 3 (with 2 year lag)
7 participants
46 participants

PRIMARY outcome

Timeframe: The case index date (ID) was the date of incident pancreatic cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control ID was the date at which the follow-up time from his/her cohort entry was the same as that for the case

Population: Cases and controls were drawn from the GPRD study cohort. Entry into the study cohort began Jan 1, 1993, or at the time of GPRD registration if after Jan 1, 1993. Follow-up ended Dec 31, 2008, or earlier if the respective cancer was diagnosed or if the participant left the GPRD for any reason including death.

Incident pancreatic cancer. Gabapentin Exposure Description: Without 2 year lag = Gabapentin exposure from cohort entry to index date. With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Tertile's without 2 year lag: Tertile 1 (0.01 - 1.55 months), Tertile 2 (1.56 - 6.44 months), and Tertile 3 (6.45 - 78.36 months). Tertile's with 2 year lag: Tertile 1 (0.01 - 1.78 months), Tertile 2 (1.79 - 7.20 months), and Tertile 3 (7.21 - 64.13 months).

Outcome measures

Outcome measures
Measure
Cases
n=3149 Participants
Cases
Controls
n=30026 Participants
Controls
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin
Never (without 2 year lag)
3093 participants
29773 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin
Tertile 1 (without 2 year lag)
28 participants
83 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin
Tertile 2 (without 2 year lag)
14 participants
79 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin
Tertile 3 (without 2 year lag)
14 participants
91 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin
Never (with 2 year lag)
3125 participants
29883 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin
Tertile 1 (with 2 year lag)
13 participants
44 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin
Tertile 2 (with 2 year lag)
4 participants
47 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin
Tertile 3 (with 2 year lag)
7 participants
52 participants

PRIMARY outcome

Timeframe: The case index date (ID) was the date of incident pancreatic cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control ID was the date at which the follow-up time from his/her cohort entry was the same as that for the case

Population: Cases and controls were drawn from the GPRD study cohort. Entry into the study cohort began Jan 1, 1993, or at the time of GPRD registration if after Jan 1, 1993. Follow-up ended Dec 31, 2008, or earlier if the respective cancer was diagnosed or if the participant left the GPRD for any reason including death.

Incident pancreatic cancer. Gabapentin Exposure Description: Without 2 year lag = Gabapentin exposure from cohort entry to index date. With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Tertile's without 2 year lag: Tertile 1 (0.01 - 33.6 grams), Tertile 2 (33.7 - 185.0 grams), and Tertile 3 (185.1 - 7500.2 grams). Tertile's with 2 year lag: Tertile 1 (0.01 - 39.0 grams), Tertile 2 (39.1 - 210.0 grams), and Tertile 3 (210.1 - 5623.8 grams).

Outcome measures

Outcome measures
Measure
Cases
n=3149 Participants
Cases
Controls
n=30026 Participants
Controls
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin
Never (without 2 year lag)
3093 participants
29773 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin
Tertile 1 (without 2 year lag)
28 participants
88 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin
Tertile 2 (without 2 year lag)
14 participants
74 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin
Tertile 3 (without 2 year lag)
14 participants
91 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin
Never (with 2 year lag)
3125 participants
29883 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin
Tertile 1 (with 2 year lag)
11 participants
46 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin
Tertile 2 (with 2 year lag)
7 participants
47 participants
Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin
Tertile 3 (with 2 year lag)
6 participants
50 participants

PRIMARY outcome

Timeframe: The case index date (ID) was the date of incident renal cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control ID was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

Population: Cases and controls were drawn from the GPRD study cohort. Entry into the study cohort began Jan 1, 1993, or at the time of GPRD registration if after Jan 1, 1993. Follow-up ended Dec 31, 2008, or earlier if the respective cancer was diagnosed or if the participant left the GPRD for any reason including death.

Incident renal cancer. Gabapentin Exposure Description: Without 2 year lag = Gabapentin prescription from cohort entry to index date. With 2 year lag = Gabapentin prescription from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer).

Outcome measures

Outcome measures
Measure
Cases
n=1981 Participants
Cases
Controls
n=19046 Participants
Controls
Number of Renal Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin
Never (with 2 year lag)
1968 participants
18970 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin
Ever (without 2 year lag)
32 participants
166 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin
Never (without 2 year lag)
1949 participants
18880 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin
Ever (with 2 year lag)
13 participants
76 participants

PRIMARY outcome

Timeframe: The case index date (ID) was the date of incident renal cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control ID was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

Population: Cases and controls were drawn from the GPRD study cohort. Entry into the study cohort began Jan 1, 1993, or at the time of GPRD registration if after Jan 1, 1993. Follow-up ended Dec 31, 2008, or earlier if the respective cancer was diagnosed or if the participant left the GPRD for any reason including death.

Incident renal cancer. Gabapentin Exposure Description: Without 2 year lag = Gabapentin exposure from cohort entry to index date. With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Tertiles without 2 year lag: Tertile 1 (1-2 prescriptions),Tertile 2 (3-8 prescriptions), and Tertile 3 (9-218 prescriptions). Tertile's with 2 year lag: Tertile 1 (1-2 prescriptions), Tertile 2 (3-10 prescriptions),Tertile 3 (11-191 prescriptions).

Outcome measures

Outcome measures
Measure
Cases
n=1981 Participants
Cases
Controls
n=19046 Participants
Controls
Number of Renal Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions
Never (without 2 year lag)
1949 participants
18880 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions
Tertile 1 (without 2 year lag)
16 participants
58 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions
Tertile 2 (without 2 year lag)
11 participants
55 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions
Tertile 3 (without 2 year lag)
5 participants
53 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions
Never (with 2 year lag)
1968 participants
18970 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions
Tertile 1 (with 2 year lag)
6 participants
27 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions
Tertile 2 (with 2 year lag)
4 participants
28 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions
Tertile 3 (with 2 year lag)
3 participants
21 participants

PRIMARY outcome

Timeframe: The case index date (ID) was the date of incident renal cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control ID was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

Population: Cases and controls were drawn from the GPRD study cohort. Entry into the study cohort began Jan 1, 1993, or at the time of GPRD registration if after Jan 1, 1993. Follow-up ended Dec 31, 2008, or earlier if the respective cancer was diagnosed or if the participant left the GPRD for any reason including death.

Incident renal cancer. Gabapentin Exposure Description: Without 2 year lag = Gabapentin exposure from cohort entry to index date. With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Tertile's without 2 year lag: Tertile 1 (0.01 - 1.55 months), Tertile 2 (1.56 - 6.44 months), and Tertile 3 (6.45 - 78.36 months). Tertile's with 2 year lag: Tertile 1 (0.01 - 1.78 months), Tertile 2 (1.79 - 7.20 months), and Tertile 3 (7.21 - 64.13 months).

Outcome measures

Outcome measures
Measure
Cases
n=1981 Participants
Cases
Controls
n=19046 Participants
Controls
Number of Renal Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin
Never (without 2 year lag)
1949 participants
18880 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin
Tertile 1 (without 2 year lag)
15 participants
44 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin
Tertile 2 (without 2 year lag)
10 participants
67 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin
Tertile 3 (without 2 year lag)
7 participants
55 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin
Never (with 2 year lag)
1968 participants
18970 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin
Tertile 1 (with 2 year lag)
6 participants
23 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin
Tertile 2 (with 2 year lag)
3 participants
31 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin
Tertile 3 (with 2 year lag)
4 participants
22 participants

PRIMARY outcome

Timeframe: The case index date (ID) was the date of incident renal cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control ID was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

Population: Cases and controls were drawn from the GPRD study cohort. Entry into the study cohort began Jan 1, 1993, or at the time of GPRD registration if after Jan 1, 1993. Follow-up ended Dec 31, 2008, or earlier if the respective cancer was diagnosed or if the participant left the GPRD for any reason including death.

Incident renal cancer. Gabapentin Exposure Description: Without 2 year lag = Gabapentin exposure from cohort entry to index date. With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Tertile's without 2 year lag: Tertile 1 (0.01 - 33.6 grams), Tertile 2 (33.7 - 185.0 grams), and Tertile 3 (185.1 - 7500.2 grams). Tertile's with 2 year lag: Tertile 1 (0.01 - 39.0 grams), Tertile 2 (39.1 - 210.0 grams), and Tertile 3 (210.1 - 5623.8 grams).

Outcome measures

Outcome measures
Measure
Cases
n=1981 Participants
Cases
Controls
n=19046 Participants
Controls
Number of Renal Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin
Never (without 2 year lag)
1949 participants
18880 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin
Tertile 1 (without 2 year lag)
9 participants
45 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin
Tertile 2 (without 2 year lag)
17 participants
63 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin
Tertile 3 (without 2 year lag)
6 participants
58 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin
Never (with 2 year lag)
1968 participants
18970 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin
Tertile 1 (with 2 year lag)
5 participants
24 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin
Tertile 2 (with 2 year lag)
5 participants
26 participants
Number of Renal Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin
Tertile 3 (with 2 year lag)
3 participants
26 participants

Adverse Events

Pancreatic Cancer Cases

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Pancreatic Cancer Controls

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Renal Cancer Cases

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Renal Cancer Controls

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

GSK Response Center

GlaxoSmithKline

Phone: 866-435-7343

Results disclosure agreements

  • Principal investigator is a sponsor employee GSK agreements may vary with individual investigators, but will not prohibit any investigator from publishing. GSK supports the publication of results from all centers of a multi-center trial but requests that reports based on single-site data not precede the primary publication of the entire clinical trial.
  • Publication restrictions are in place

Restriction type: OTHER