Table 3.

Adjusted rate ratios for serious cardiovascular events, associated with ADHD medication use, new user cohort, remote use comparison

Medication status	Person- yrs	Number Events	Rate/1,000 person-yrs	Unadjusted RR	Adjusted matching variables RRa	Adjusted RRb	95%CI
MI
Current use	55,533.9	77	1.39	0.67	1.04	1.08	0.81 – 1.45
Type of medication
Amphetamines	23,265.6	24	1.03	0.50	0.86	0.94	0.60 – 1.46
Methylphenidate	23,930.8	42	1.76	0.84	1.23	1.26	0.88 – 1.80
Atomoxetine	6,475.3	9	1.39	0.67	1.06	1.06	0.54 – 2.10
Pemoline	1,114.4	2	1.79	0.86	0.76	0.75	0.18 – 3.03
Multiple	747.7	0	0.00	--	--	--	--
Durationc
1–30 days	7,526.3	11	1.46	0.70	1.26	1.31	0.70 – 2.43
31–90 days	9,656.8	11	1.14	0.55	1.01	1.06	0.57 – 1.96
91–182 days	9,556.3	8	0.84	0.40	0.71	0.75	0.36 – 1.53
183–365 days	11,221.9	16	1.43	0.68	1.13	1.19	0.70 – 2.01
366+ days	16,425.2	29	1.77	0.85	1.09	1.15	0.76 – 1.73
Indeterminate use	31,090.0	52	1.67	0.80	1.27	1.32	0.95 – 1.84
Former use	35,087.7	55	1.57	0.75	1.08	1.08	0.78 – 1.49
Remote use	55,194.2	115	2.08	1.00	1.00	1.00	reference
SCDd
Current use	52,203.2	15	0.29	0.34	0.61	0.62	0.34 – 1.11
Type of medication
Amphetamines	22,002.7	3	0.14	0.16	0.34	0.38	0.12 – 1.22
Methylphenidate	22,056.6	8	0.36	0.43	0.70	0.69	0.32 – 1.46
Atomoxetine	6,348.4	3	0.47	0.57	0.95	0.90	0.28 – 2.91
Pemoline	1,091.6	1	0.92	1.10	0.90	0.93	0.13 – 6.77
Multiple	703.9	0	0.00	--	--	--	--
Durationc
1–30 days	7,217.4	2	0.28	0.33	0.67	0.68	0.16 – 2.81
31–90 days	9,195.9	2	0.22	0.26	0.56	0.56	0.14 – 2.33
91–182 days	9,026.0	4	0.44	0.53	1.09	1.11	0.40 – 3.10
183–365 days	10,511.3	1	0.10	0.11	0.22	0.22	0.03 – 1.62
366+ days	15,129.8	5	0.33	0.40	0.57	0.57	0.22 – 1.43
Indeterminate use	29,752.7	13	0.44	0.52	0.94	0.96	0.52 – 1.79
Former use	33,877.6	16	0.47	0.57	0.89	0.88	0.50 – 1.56
Remote use	53,926.6	45	0.83	1.00	1.00	1.00	reference
Strokee
Current use	54,569.3	41	0.75	0.73	1.10	1.09	0.72 – 1.64
Type of medication
Amphetamines	22,965.2	10	0.44	0.43	0.72	0.77	0.39 – 1.53
Methylphenidate	23,335.7	26	1.11	1.09	1.53	1.44	0.90 – 2.30
Atomoxetine	6,429.4	3	0.47	0.46	0.66	0.64	0.20 – 2.04
Pemoline	1,099.7	2	1.82	1.78	1.48	1.39	0.34 – 5.72
Multiple	739.3	0	0.00	--	--	--	--
Durationc
1–30 days	7,421.0	4	0.54	0.53	0.93	0.92	0.33 – 2.53
31–90 days	9,511.8	6	0.63	0.62	1.10	1.08	0.46 – 2.51
91–182 days	9,398.0	9	0.96	0.94	1.59	1.55	0.76 – 3.14
183–365 days	11,018.6	4	0.36	0.35	0.56	0.55	0.20 – 1.53
366+ days	16,087.6	16	0.99	0.97	1.19	1.21	0.69 – 2.11
Indeterminate use	30,657.1	20	0.65	0.64	1.00	1.00	0.60 – 1.67
Former use	34,644.6	26	0.75	0.73	1.05	1.04	0.65 – 1.65
Remote use	54,702.5	56	1.02	1.00	1.00	1.00	reference
MI, SCD or stroked,e
Current use	52,094.6	125	2.40	0.65	1.00	1.02	0.82 – 1.28
Type of medication
Amphetamines	21,955.8	37	1.69	0.46	0.80	0.87	0.61 – 1.23
Methylphenidate	22,008.8	69	3.14	0.85	1.22	1.20	0.91 – 1.59
Atomoxetine	6,340.4	14	2.21	0.60	0.93	0.91	0.53 – 1.56
Pemoline	1,088.1	5	4.60	1.25	1.07	1.02	0.42 – 2.49
Multiple	701.4	0	0.00	--	--	--	--
Durationc
1–30 days	7,215.7	16	2.22	0.60	1.08	1.10	0.66 – 1.83
31–90 days	9,191.7	19	2.07	0.56	1.04	1.05	0.66 – 1.69
91–182 days	9,018.3	18	2.00	0.54	0.96	0.97	0.60 – 1.57
183–365 days	10,494.1	20	1.91	0.52	0.85	0.86	0.54 – 1.37
366+ days	15,055.5	47	3.12	0.85	1.06	1.10	0.80 – 1.51
Indeterminate use	29,694.2	82	2.76	0.75	1.19	1.22	0.94 – 1.58
Former use	33,774.3	97	2.87	0.78	1.13	1.11	0.87 – 1.41
Remote use	53,450.1	197	3.69	1.00	1.00	1.00	reference

Abbreviations: MI, myocardial infarction; SCD, sudden cardiac death; RR, rate ratio; CI, confidence interval; CRS, cardiovascular risk score; KP, Kaiser Permanente

^aAdjusted for site, age, sex, and calendar year (ie, matching variables).

^bAdjusted for site, age, sex, calendar year, and CRS (some variables within score are time-varying).

^cDuration does not include pemoline use (pemoline only and pemoline with other ADHD medications).

^dAnalyses excluded the three HMORN sites (Fallon Community, KP Georgia, KP Northwest) that did not provide data on SCD endpoints.

^eAnalyses excluded the two HMORN sites (Fallon Community, KP Georgia) that did not provide data on stroke endpoints.