Table 1.

Prevalence of prescription drug use in prior 30 days among US adults (age ≥ 20y), 2011–2012 (n=5,558)^a

	Overall	Any prescriptions			Polypharmacy (≥5 prescriptions)
	n	n	%b	95% CI	n	%b	95% CI
Overall	5,558	3,144	59	55, 62	917	15	13,17
Age Group (years)
20–39	1,957	596	35	32, 39	47	3.1	2.1, 4.6
40–64	2,352	1,428	65	62, 67	372	15	13, 17
≥65	1,249	1,120	90	87, 93	498	39	35, 44
Sex
Male	2,739	1,398	52	48, 57	418	13	10, 16
Female	2,819	1,746	65	62, 67	499	16	14, 19
Race/ethnicity
Non-Hispanic white	2,040	1,377	66	63, 69	440	17	15, 20
Non-Hispanic black	1,455	835	52	49, 55	266	14	12, 17
Non-Hispanic Asian	794	335	41	36, 45	54	6.0	4.0, 8.7
Mexican American	539	214	33	28, 38	56	6.8	4.2, 10
Other Hispanic	578	305	41	36, 45	77	8.5	6.0, 12
Other	152	78	51	38, 63	24	17	8.6, 32
Education
< High school	1,331	806	57	50, 64	296	19	16, 23
High school	1,169	658	58	53, 64	196	15	12, 19
Some college	1,657	901	57	52, 62	264	15	13, 19
≥ College	1,396	776	61	57, 65	160	12	9.2, 14
Family income-to-poverty ratioc
<1 (lowest income)	1,303	677	49	43, 54	241	16	11, 21
1– <2	1,326	755	59	52, 65	258	18	15, 21
2– <4	1,167	662	58	51, 64	173	15	11, 19
≥4 (highest income)	1,267	760	65	60, 69	148	12	10, 14
Insurance status (age<65yd)
No insurance	1,259	369	31	25, 38	47	3.6	2.1, 6.0
Government only	872	544	64	59, 70	201	21	17, 25
Any private insurance	2,175	1,110	57	54, 60	171	9.1	7.5, 11
Body Mass Indexe(kg/m2)
<18.5	103	50	59	50, 68	12	18	9.8, 32
18– <25	1,577	768	52	48, 57	148	8.4	5.5, 13
25– <30	1,684	939	57	52, 62	245	12	10, 15
30– <35	1,066	1,066	62	58, 66	212	17	15, 19
35– <40	451	284	68	60, 75	109	24	18, 30
≥40	354	250	73	66, 78	117	29	24, 35

^aTable 1 presents the percent of the population using any prescriptions and the percent using ≥ 5 prescriptions within given socio-demographic groups. For example, 19% of adults with less than a high school education reported taking 5 or more prescription drugs.

^bAll data are weighted to be nationally representative.

^cRatio of family income to federal poverty level. In 2012, the federal poverty level for a family of 4 was $22,050. A family of 4 with an income of $40,000 would have a family income-to-poverty ratio of 1.81, indicating that their income is 181% greater than the federal poverty level.

^dInformation on insurance status was obtained from the health insurance questionnaire, assessing whether the individual was covered by health insurance at the time of the survey. Limited to adults age<65y since 98.9% of adults age ≥ 65y reported having some form of health insurance.

^eBody mass index was calculated based on measured heights and weights. As measured heights and weights were available for 94.2% of respondents Mobile Exam Center weights were used for analyses of body mass index (interview weights were used in all other cases).