Coffee Intake and Incidence of Erectile Dysfunction

David S. Lopez; Lydia Liu; Eric B. Rimm; Konstantinos K. Tsilidis; Marcia de Oliveira Otto; Run Wang; Steven Canfield; Edward Giovannucci

Disclosures

Am J Epidemiol. 2018;187(5):951-959.

Abstract and Introduction

Abstract

Coffee intake is suggested to have a positive impact on chronic diseases, yet its role in urological diseases such as erectile dysfunction (ED) remains unclear. We investigated the association of coffee intake with incidence of ED by conducting the Health Professionals Follow-Up Study, a prospective analysis of 21,403 men aged 40–75 years old. Total, regular, and decaffeinated coffee intakes were self-reported on food frequency questionnaires. ED was assessed by mean values of questionnaires in 2000, 2004 and 2008. Multivariable adjusted Cox proportional hazards models were used to compute hazard ratios for patients with incident ED (n = 7,298). No significant differences were identified for patients with incident ED after comparing highest (≥4 cups/day) with lowest (0 cups/day) categories of total (hazard ratio (HR) = 1.00, 95% confidence interval (CI): 0.90, 1.11) and regular coffee intakes (HR = 1.00, 95% CI: 0.89, 1.13). When comparing the highest category with lowest category of decaffeinated coffee intake, we found a 37% increased risk of ED (HR = 1.37, 95% CI: 1.08, 1.73), with a significant trend (P trend = 0.02). Stratified analyses also showed an association among current smokers (P trend = 0.005). Overall, long-term coffee intake was not associated with risk of ED in a prospective cohort study.

Introduction

Coffee is a rich source of caffeine, antioxidants and anti-inflammatory compounds,^[1–4] and has been implicated to have a potentially beneficial role against chronic diseases. Yet, the role of coffee intake in urological diseases, specifically in erectile dysfunction (ED), remains undetermined.^[5–9] The prevalence of ED in American men aged 20 years or older is 18.4%, which suggests that more than 18 million people are affected.^[10,11] Further, in a prospective study, 17.7% of men (aged 40–75 years) reported incident ED during a 14-year follow-up.^[12] Among older men, these numbers substantially increase, which affects overall quality of life.^[11,13,14]

An inverse association between coffee intake and improved erectile function is biologically plausible. In addition to being a major source of polyphenols, coffee has the potential to increase testosterone levels,^[15–17] initiate a series of pharmacologic reactions that lead to the relaxation of the cavernous smooth muscle, and improve blood supply through penile arteries.^[18] In a previous cross-sectional analysis using the National Health and Nutrition and Examination Survey from 2001–2004, a nationally representative sample of the US noninstitutionalized male population, the equivalent of 2–3 cups of coffee per day was associated with a lower likelihood of ED.^[19] A further investigation of this association was conducted among men with comorbidities such as obesity, hypertension and diabetes, which are strong risk factors for ED. The findings remained the same among obese and hypertensive men, but not among men with diabetes.

Given the inherent limitations of the cross-sectional study design and a relatively small total sample size (n = 3,724) in the National Health and Nutrition and Examination Survey analyses, we decided to investigate prospectively the association of caffeinated and decaffeinated beverages with risk of ED in the Health Professionals Follow-up Study (HPFS). In the HPFS, we used an analytic sample of 21,403 men, 7,298 patients with incident ED, and a follow-up period of 10 years. Additionally, we investigated these associations among men with lifestyle factors and comorbid conditions such as obesity, hypertension, diabetes, history of smoking, and marital status.

1 2 3 4

Next Section

Abstract and Introduction
Methods
Results
Discussion
References

Table 1. Baseline Age-Adjusted Characteristics by Total Coffee Consumption, Health Professionals Follow-up Study, 1998–2010
Characteristic	Coffee Intake, cups/day
	None(n = 2,753)		0.01–0.50(n = 2,506)		0.50–0.99(n = 2,208)		1.00–3.99(n = 11,576)		≥4.00 (n = 2,360)		P for Trend
	%	Mean (SD)	%	Mean (SD)	%	Mean (SD)	%	Mean (SD)	%	Mean (SD)	P for Trend
Age, years		60.3 (8.1)		61.3 (8.5)		62.6 (8.7)		62.5 (8.5)		61.2 (7.6)
BMI^a		25.5 (3.7)		25.3 (3.4)		25.7 (3.3)		26.1 (3.4)		26.5 (3.5)	<0.0001
Physical activity, METs/week		37.9 (41.1)		37.9 (43.1)		38.2 (40.1)		36.4 (39.2)		33.8 (36.5)	<0.0001
Currently married	91		88		90		89		90		0.71
Smoking status
Never	79		68		61		47		34		<0.0001
Past	19		30		37		49		55		<0.0001
Current	2		2		2		5		12		<0.0001
Self-reported disease
Hypertension	13		14		16		15		12		0.59
High cholesterol	40		45		46		46		43		<0.0001
Difficulty falling asleep^b	21		20		21		21		19		0.99
Waking during the night^b	55		54		58		59		58		<0.0001
Not feeling rested upon waking^b	23		23		23		23		24		0.99
Medication
Low blood pressure	19		23		25		24		20		0.005
Lower cholesterol	11		11		14		13		12		0.0002
Sleep medication^b	3		3		3		4		3		0.04
Alcohol consumption, g/day		4.7 (9.7)		8.4 (12.1)		9.7 (12.4)		13.0 (14.4)		13.8 (15.7)	<0.0001
Calories, kcal/day		1,972 (604)		1,967 (394)		1,944 (601)		2.011 (602)		2.092 (692)	<0.0001
AHEI score		49.7 (11.7)		52.7 (11.4)		52.2 (11.2)		51.3 (11)		49.8 (10.7)	0.72
Regular coffee		0 (0)		0.1 (0.1)		0.4 (0.3)		1.6 (1.0)		3.6 (1.5)	<0.0001
Decaffeinated coffee		0 (0)		0.1 (0.1)		0.3 (0.3)		0.7 (0.8)		1.3 (1.5)	<0.0001

Abbreviations: AHEI, Alternative Healthy Eating Index; BMI, body mass index; MET, metabolic equivalent of task; SD, standard deviation.
^aWeight (kg)/height (m)².
^bVariables were ascertained in 2004 questionnaire.

Table 2. Baseline Age-Adjusted Characteristics by Regular Coffee Consumption, Health Professionals Follow-up Study, 1998–2010
Characteristics	Coffee Intake, cups/day
	None(n = 4,058)		0.01–0.50(n = 4,112)		0.50–0.99(n = 2,732)		1.00–3.99(n = 9,167)		≥4.00 (n = 1,334)		P for Trend
	%	Mean (SD)	%	Mean (SD)	%	Mean (SD)	%	Mean (SD)	%	Mean (SD)	P for Trend
Age, years		61.7 (8.7)		62.3 (8.5)		62.5 (8.6)		62.0 (8.3)		60.3 (7.2)
BMI^a		25.6 (3.5)		25.6 (3.3)		26.0 (3.5)		26.2 (3.4)		26.4 (3.4)	<0.0001
Physical activity, METs/week		38.3 (42.8)		37.4 (39.3)		36.6 (38.9)		36.2 (39.3)		32.2 (34.9)	<0.0001
Currently married	91		90		89		89		88		<0.0001
Smoking status
Never	72		61		52		45		34		<0.0001
Past	26		36		45		49		52		<0.0001
Current	2		3		4		5		14		<0.0001
Self-reported disease
Hypertension	15		16		17		14		10		0.0002
High cholesterol	43		47		47		45		42		0.47
Difficulty falling asleep^b	22		22		24		20		21		0.09
Waking during the night^b	56		57		59		59		56		0.02
Not feeling rested upon waking^b	23		24		23		23		22		0.29
Medication
Low blood pressure	22		24		25		22		18		0.10
Lower cholesterol	12		13		14		13		11		0.97
Sleep medication^b	3		3		3		4		3		0.40
Alcohol consumption, g/day		6.2 (11.1)		10.0 (13.3)		10.9 (12.6)		13.5 (14.7)		13.9 (15.7)	<0.0001
Calories, kcal/day		1,944 (587)		1,976 (605)		1,980 (607)		2,033 (606)		2,100 (642)	<0.0001
AHEI score		50.7 (11.7)		52.3 (11.2)		52.2 (10.9)		50.9 (11)		48.8 (10.6)	<0.0001
Total coffee		0.3 (0.7)		0.9 (1.0)		1.5 (0.9)		2.7 (1.0)		5.0 (0.9)	<0.0001
Decaffeinated coffee		0.3 (0.7)		0.7 (1.0)		0.8 (0.9)		0.6 (0.8)		0.3 (0.6)	<0.0001

Abbreviations: AHEI, Alternative Healthy Eating Index; BMI, body mass index; MET; metabolic equivalent of task; SD, standard deviation.
^aWeight (kg)/height (m)².
^bVariables were ascertained in the 2004 questionnaire.

Table 3. Baseline Age-Adjusted Characteristics by Decaffeinated Coffee Consumption, Health Professionals Follow-up Study, 1998–2010
Characteristic	Coffee Intake, cups/day
	None(n = 6,787)		0.01–0.50(n = 7,280)		0.50–0.99(n = 3,041)		1.00–3.99(n = 4,088)		≥4.00(n = 207)		P for Trend
	%	Mean (SD)	%	Mean (SD)	%	Mean (SD)	%	Mean (SD)	%	Mean (SD)	P for Trend
Age, years		61.2 (8.3)		61.5 (8.3)		62.6 (8.5)		63.4 (8.3)		63.3 (8.3)
BMI^a		25.9 (3.6)		25.8 (3.3)		26.0 (3.3)		26.3 (3.4)		26.8 (3.5)	<0.0001
Physical activity, METs/week		36.1 (40)		37.2 (40.8)		36.4 (36.9)		36.6 (39.1)		34.6 (38.9)	0.60
Currently married	88		89		90		92		95		<0.0001
Smoking status
Never	59		56		51		41		31		<0.0001
Past	35		41		45		53		59		<0.0001
Current	6		3		4		5		11		0.90
Self-reported disease
Hypertension	13		13		16		17		20		<0.0001
High cholesterol	41		45		47		49		51		<0.0001
Difficulty falling asleep^b	19		22		22		21		23		0.03
Waking during the night^b	53		58		62		62		62		<0.0001
Not feeling rested upon waking^b	21		23		25		24		17		0.008
Medication
Low blood pressure	20		22		26		26		25		<0.0001
Lower cholesterol	11		12		14		15		12		<0.0001
Sleep medication^b	3		3		3		4		3		0.0007
Alcohol consumption, g/day		9.8 (14.3)		11.1 (13.1)		11.8 (13.4)		12.7 (14.7)		14.6 (17.2)	<0.0001
Calories, kcal/day		1,992 (614)		2,014 (602)		2,000 (611)		1,999 (595)		2,110 (604)	0.40
AHEI score		49.3 (11.5)		52.2 (10.9)		52.0 (11)		51.8 (10.8)		51.0 (10.4)	<0.0001
Regular coffee		1.3 (1.6)		1.4 (1.3)		1.3 (1.2)		1.2 (1.2)		1.1 (1.2)	<0.0001
Decaffeinated coffee		1.3 (1.6)		1.6 (1.3)		2.0 (1.2)		3.0 (1.3)		5.6 (1.3)	<0.0001

Table 4. Multivariable Associations of Cumulative Average Intakes of Total, Regular, and Decaffeinated Coffee With Erectile Dysfunction ( n = 21,403), Health Professionals Follow-up Study, 1998–2010
Coffee Type and Consumption	No. of Person-Years	No. of ED Cases	Model 1^a			Model 2^b
Coffee Type and Consumption	No. of Person-Years	No. of ED Cases	HR	95% CI	P for Trend	HR	95% CI	P for Trend
Total coffee, cups/day					0.004			0.37
None^c	24,630	829	1.00	Referent		1.00	Referent
0.01–0.50	23,167	764	0.92	0.83, 1.01		0.93	0.84, 1.03
0.50–0.99	19,705	738	0.94	0.85, 1.03		0.92	0.83, 1.02
1.00–3.99	103,629	4,242	1.04	0.96, 1.12		0.99	0.92, 1.08
≥4.00	18,861	725	1.08	0.97, 1.19		1.00	0.90, 1.11
Regular coffee, cups/day					0.09			0.90
None^c	34,791	1,243	1.00	Referent		1.00	Referent
0.01–0.50	36,999	1,424	1.04	0.97, 1.12		1.05	0.97, 1.13
0.50–0.99	23,978	963	1.05	0.96, 1.14		1.03	0.94, 1.12
1.00–3.99	83,857	3,279	1.06	0.99, 1.13		1.03	0.96, 1.10
≥4.00	10,365	359	1.07	0.95, 1.20		1.00	0.89, 1.13
Decaffeinated coffee, cups/day					0.0005			0.02
None^c	58,716	2,069	1.00	Referent		1.00	Referent
0.01–0.50	69,458	2,515	0.99	0.93, 1.05		1.00	0.94, 1.06
0.50–0.99	26,540	1,074	1.03	0.96, 1.11		1.02	0.95, 1.10
1.00–3.99	34,000	1,566	1.09	1.02, 1.17		1.06	0.99, 1.13
≥4.00	1,278	74	1.54	1.22, 1.95		1.37	1.08, 1.73

Abbreviations: CI, confidence interval; ED, erectile dysfunction; HR, hazard ratio.
^aModel 1 was adjusted for age in months and calendar time.
^bModel 2 was adjusted for the variables in model 1 and smoking (never, past, or current, categorized as 1–14, 15–24, ≥25 cigarettes/day), body mass index (weight in kilometers divided by height in meters squared; <25.0, 25.0–29.9, or ≥30.0), alcohol consumption (grams/day; 0, 0.1–4.9, 5.0–14.9, 15.0–29.9, or ≥30.0), total physical activity (metabolic equivalent of tasks per week; quintiles), history of diabetes (yes vs. no), history of hypertension (yes vs. no), history of hypercholesterolemia (yes vs. no), history of cardiovascular disease (yes vs. no), energy intake (kcal/day; quintiles), Alternative Healthy Eating Index score (quintiles), marital status (married, divorced, separated, widowed, or never married), race (white, African-American, Asian-American, or other), difficulty of falling into sleep (yes vs. no), waking during the night (yes vs. no), not feeling rested upon waking (yes vs. no), and use of cholesterol-lowering, blood pressure–lowering, or sleep-enhancing medication (yes vs. no).
^cIncluded men who drank no regular or decaffeinated coffee.

Table 5. Four-Year Latent Period in the Multivariable Associations ^a of Total, Regular, and Decaffeinated Coffee Intakes With Erectile Dysfunction, Health Professionals Follow-up Study, 2002–2010
Type of Coffee	Coffee Intake, cups/day
	No Coffee^b		0.01–0.50		0.50–0.99		1.00–3.99		≥4.00		P for Trend
	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI	P for Trend
Total	1.00	Referent	0.87	0.77, 0.98	0.86	0.76, 0.97	0.93	0.85, 1.02	0.92	0.81, 1.04	0.63
Regular	1.00	Referent	0.93	0.84, 1.02	0.98	0.88, 1.09	0.98	0.91, 1.07	0.89	0.77, 1.02	0.74
Decaffeinated	1.00	Referent	0.95	0.89, 1.03	0.95	0.87, 1.05	0.99	0.91, 1.08	1.43	1.10, 1.87	0.64

Abbreviations: CI, confidence interval; HR, hazard ratio.
^aModels were adjusted for age in months, calendar time, smoking (never, past, or current, categorized as 1–14, 15–24, ≥25 cigarettes/day), body mass index (weight in kilometers divided by height in meters squared; <25.0, 25.0–29.9, or ≥30.0), alcohol consumption (grams/day; 0, 0.1–4.9, 5.0–14.9, 15.0–29.9, or ≥30.0), total physical activity (metabolic equivalent of tasks per week; quintiles), history of diabetes (yes vs. no), history of hypertension (yes vs. no), history of hypercholesterolemia (yes vs. no), history of cardiovascular disease (yes vs. no), energy intake (kcal/day; quintiles), Alternative Healthy Eating Index score (quintiles), marital status (married, divorced, separated, widowed, or never married), race (white, African-American, Asian-American, or other), difficulty of falling into sleep (yes vs. no), waking during the night (yes vs. no), not feeling rested upon waking (yes vs. no), and use of cholesterol-lowering, blood pressure–lowering, or sleep-enhancing medication (yes vs. no).
^bIncluded men who drank no regular or decaffeinated coffee.

Table 6. Associations ^a of Cumulative Average Intakes of Total Coffee, Regular Coffee, and Decaffeinated Coffee With Erectile Dysfunction, Stratified by Smoking Status, Health Professionals Follow-up Study, 1998–2010
Type of Coffee and Smoking Status	Coffee Intake, cups/day
	No Coffee^b		0.01–0.50		0.50–0.99		1.00–3.99		≥4.00		P for Trend	P for Interaction
	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI	P for Trend	P for Interaction
Total coffee												0.11
Never smoker	1.00	Referent	0.98	0.87, 1.10	0.91	0.80, 1.04	0.98	0.89, 1.08	0.99	0.84, 1.15	0.78
Past smoker	1.00	Referent	0.90	0.74, 1.09	0.97	0.80, 1.17	1.01	0.86, 1.17	1.02	0.85, 1.22	0.23
Current smoker	1.00	Referent	0.72	0.27, 1.93	0.72	0.26, 2.02	1.45	0.72, 2.95	1.23	0.59, 2.56	0.14
Regular coffee												0.80
Never smoker	1.00	Referent	1.01	0.92, 1.12	0.98	0.87, 1.10	1.00	0.92, 1.10	1.06	0.87, 1.29	0.86
Past smoker	1.00	Referent	1.11	0.97, 1.26	1.09	0.95, 1.25	1.07	0.95, 1.20	1.05	0.88, 1.25	0.76
Current smoker	1.00	Referent	1.23	0.62, 2.44	1.85	0.93, 3.70	1.50	0.84, 2.67	1.20	0.63, 2.27	0.55
Decaffeinated coffee												0.06
Never smoker	1.00	Referent	1.00	0.92, 1.09	0.97	0.87, 1.08	1.02	0.92, 1.13	1.30	0.82, 2.06	0.72
Past smoker	1.00	Referent	0.94	0.86, 1.03	1.00	0.89, 1.11	1.00	0.91, 1.10	1.31	0.98, 1.74	0.34
Current smoker	1.00	Referent	1.54	1.07, 2.21	1.54	0.98, 2.40	1.63	1.13, 2.35	2.64	0.88, 7.87	0.005

Abbreviations: CI, confidence interval; HR, hazard ratio.
^aIncluded men who drank no regular or decaffeinated coffee.
^bModels were adjusted for age in months, calendar time, smoking (never, past, or current, categorized as 1–14, 15–24, ≥25 cigarettes/day), body mass index (weight in kilometers divided by height in meters squared; <25.0, 25.0–29.9, or ≥30.0), alcohol consumption (grams/day; 0, 0.1–4.9, 5.0–14.9, 15.0–29.9, or ≥30.0), total physical activity (metabolic equivalent of tasks per week; quintiles), history of diabetes (yes vs. no), history of hypertension (yes vs. no), history of hypercholesterolemia (yes vs. no), history of cardiovascular disease (yes vs. no), energy intake (kcal/day; quintiles), Alternative Healthy Eating Index score (quintiles), marital status (married, divorced, separated, widowed, or never married), race (white, African-American, Asian-American, or other), difficulty of falling into sleep (yes vs. no), waking during the night (yes vs. no), not feeling rested upon waking (yes vs. no), and use of cholesterol-lowering, blood pressure–lowering, or sleep-enhancing medication (yes vs. no).

Web Table 1. Stratified by BMI (BMI<25, BMI 25–29, BMI≥30) the association of cumulative average intake of total coffee, regular coffee, and decaffeinated coffee with erectile dysfunction (ED) in the Health Professionals Follow-Up Study, 1998–2010
	Coffee Intake, cups/day
Type of coffee and BMI categories	No coffee^a		<0.5		0.5–0.99		1-3.99		≥4		P for trend	P for interaction
	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI
Total coffee												0.07
BMI < 25
Model 1^b	1.00	Referent	0.88	0.76, 1.02	0.88	0.75, 1.02	0.93	0.82, 1.04	0.93	0.78, 1.11	0.63
BMI 25–29
Model 1	1.00	Referent	0.92	0.74, 1.09	0.92	0.80, 1.17	0.98	0.86, 1.17	0.97	0.85, 1.22	0.74
BMI ≥ 30
Model 1	1.00	Referent	1.40	0.27, 1.93	1.15	0.26, 2.02	1.30	0.72, 2.95	1.36	0.59, 2.56	0.08
Regular coffee												0.16
BMI <25
Model 1	1.00	Referent	0.98	0.87, 1.10	0.96	0.84, 1.10	0.98	0.88, 1.09	0.88	0.70, 1.10	0.52
BMI 25–29
Model 1	1.00	Referent	1.05	0.94, 1.19	1.04	0.91, 1.18	1.05	0.94, 1.16	1.03	0.87, 1.22	0.60
BMI ≥ 30
Model 1	1.00	Referent	1.24	0.98, 1.57	1.33	1.04, 1.71	1.15	0.94, 1.40	1.20	0.88, 1.63	0.51
Decaffeinated coffee												0.88
BMI <25
Model 1	1.00	Referent	0.93	0.85, 1.03	0.96	0.85, 1.08	1.08	0.97, 1.20	0.99	0.60, 1.63	0.17
BMI 25–29
Model 1	1.00	Referent	1.01	0.92, 1.10	1.00	0.89, 1.11	1.01	0.91, 1.11	1.61	1.19, 2.19	0.45
BMI ≥ 30
Model 1	1.00	Referent	1.13	0.96, 1.32	1.12	0.91, 1.38	1.05	0.87, 1.27	1.49	0.84, 2.65	0.45

Abbreviations: CI, confidence interval; HR, hazard ratio; BMI, body mass index
^aIncluded men who drink no regular or decaffeinated coffee.
^bModels were adjusted for age in months, calendar time, smoking (never, past, or current 1–14, 15–24, ≥25 cigarettes/d), alcohol (gm/d, 0; 0.1–4.9; 5–14.9;15-29.9;30+), total activity metabolic equivalent/week(quintiles)ls, history of diabetes (yes/no), history of hypertension (yes/no), history of hypercholesterolemia (yes/no), history of cardiovascular disease (yes/no), energy intake (kcal/d, quintiles), AHEI score(quintiles), marital status (married, divorced, separated, widowed, or never married), race (White, African-American, Asian American, Other), difficulty of falling into sleep(yes/no), wake up during night(yes/no), not feel rested when wake up (yes/no), medication for lowering cholesterol, lowering blood pressure and sleep medicine (yes/no).
^bReference group is men who drink no regular or decaffeinated coffee.

Web Table 2. Stratified by hypertension history (yes/no) the association of cumulative average intake of total coffee, regular coffee, and decaffeinated coffee with erectile dysfunction (ED) in the Health Professionals Follow-Up Study, 1998–2010
	Coffee Intake, cups/day
Type of coffee and Hypertension status	No coffee^a		<0.5		0.5–0.99		1–3.99		≥4		P for trend	P for interaction
	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI
Total coffee												0.25
Hypertension (No)
Model 1^b	1.00	Referent	0.93	0.83, 1.04	0.93	0.83, 1.04	0.97	0.89, 1.06	0.97	0.87, 1.09	0.92
Hypertension (Yes)
Model 1	1.00	Referent	1.03	0.80, 1.33	0.95	0.74, 1.22	1.08	0.88, 1.32	1.07	0.81, 1.42	0.33
Regular coffee												0.25
Hypertension (No)
Model 1	1.00	Referent	1.01	0.93, 1.10	0.97	0.88, 1.07	1.00	0.93, 1.08	1.00	0.87, 1.13	0.93
Hypertension (Yes)
Model 1	1.00	Referent	1.19	0.94, 1.19	1.32	0.91, 1.18	1.15	0.94, 1.16	0.97	0.69, 1.37	0.42
Decaffeinated coffee												0.72
Hypertension (No)
Model 1	1.00	Referent	0.99	0.93, 1.06	1.01	0.93, 1.09	1.02	0.95, 1.10	1.31	1.01, 1.70	0.28
Hypertension (Yes)
Model 1	1.00	Referent	0.97	0.84, 1.13	0.97	0.81, 1.15	1.05	0.90, 1.23	1.43	0.83, 2.44	0.38

Abbreviations: CI, confidence interval; HR, hazard ratio; BMI, body mass index
^aIncluded men who drink no regular or decaffeinated coffee.
^bModels which were adjusted for age in months, calendar time, smoking (never, past, or current 1–14, 15–24, ≥25 cigarettes/d), BMI (kg/m², <25;25-29.9;30+), alcohol (gm/d, 0; 0.1–4.9; 5–14.9;15-29.9;30+), total activity metabolic equivalent/week (quintiles), history of diabetes (yes/no), history of hypercholesterolemia (yes/no), history of cardiovascular disease (yes/no), energy intake (kcal/d, quintiles), AHEI score(quintiles), marital status (married, divorced, separated, widowed, or never married), race (White, African-American, Asian American, Other), difficulty of falling into sleep(yes/no), wake up during night(yes/no), not feel rested when wake up (yes/no), medication for lowering cholesterol, lowering blood pressure and sleep medicine (yes/no).

Web Table 3. Stratified by currently married (yes/no) the association of cumulative average intake of total coffee, regular coffee, and decaffeinated coffee with erectile dysfunction (ED) in the Health Professionals Follow-Up Study, 1998–2010
	Coffee Intake, cups/day
Type of coffee and Marital status	No coffee^a		<0.5		0.5–0.99		1–3.99		≥4		P for trend	P for interaction
	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI
Total coffee												0.32
Not Currently married
Model 1^b	1.00	Referent	1.03	0.73, 1.45	0.86	0.60, 1.23	1.07	0.81, 1.43	1.21	0.83, 1.77	0.28
Currently married
Model 1	1.00	Referent	0.93	0.83, 1.03	0.92	0.83, 1.02	0.97	0.89, 1.06	0.97	0.87, 1.08	0.94
Regular coffee												0.67
Not Currently married
Model 1	1.00	Referent	1.11	0.84, 1.46	1.14	0.85, 1.54	1.10	0.86, 1.41	1.15	0.76, 1.74	0.53
Currently married
Model 1	1.00	Referent	1.03	0.95, 1.12	1.01	0.92, 1.10	1.02	0.94, 1.09	0.99	0.87, 1.12	0.94
Decaffeinated coffee												0.08
Not Currently married
Model 1	1.00	Referent	0.99	0.82, 1.19	0.98	0.77, 1.25	1.20	0.96, 1.51	2.57	1.00, 6.59	0.10
Currently married
Model 1	1.00	Referent	0.98	0.92, 1.05	1.00	0.92, 1.08	1.01	0.94, 1.09	1.29	1.01, 1.65	0.35

Abbreviations: CI, confidence interval; HR, hazard ratio
^aIncluded men who drink no regular or decaffeinated coffee.
^bModels were adjusted for age in months, calendar time, smoking (never, past, or current 1–14, 15–24, ≥25 cigarettes/d), BMI (kg/m², <25;25-29.9;30+), alcohol (gm/d, 0; 0.1–4.9; 5–14.9;15-29.9;30+), total activity metabolic equivalent/week (quintiles), history of diabetes (yes/no), history of hypertension (yes/no), history of hypercholesterolemia (yes/no), history of cardiovascular disease (yes/no), energy intake (kcal/d, quintiles), AHEI score (quintiles), race (White, African-American, Asian American, Other), difficulty of falling into sleep(yes/no), wake up during night(yes/no), not feel rested when wake up (yes/no), medication for lowering cholesterol, lowering blood pressure and sleep medicine (yes/no).
^bReference group is men who drink no regular or decaffeinated coffee.

Web Table 4. Stratified by Alcohol: the association of cumulative average intake of total coffee, regular coffee, and decaffeinated coffee with erectile dysfunction (ED) in the Health Professionals Follow-Up Study, 1998–2010
	Coffee Intake, cups/day
Type of coffee and Alcohol intake	No coffee^a		<0.5		0.5–0.99		1–3.99		≥4		P for trend	P for interaction
	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI
Total coffee												0.70
Alcohol 0 g/day
Model 1^b	1.00	Referent	1.02	0.87, 1.20	0.98	0.82, 1.18	0.95	0.83, 1.08	1.09	0.88, 1.34	0.73
Alcohol 0.1–14.9 g/day
Model 1	1.00	Referent	0.96	0.82, 1.12	0.92	0.79, 1.07	1.04	0.92, 1.18	0.99	0.84, 1.16	0.28
Alcohol ≥15 g/day
Model 1	1.00	Referent	0.76	0.59–0.97	0.82	0.64–1.04	0.85	0.70, 1.05	0.85	0.67, 1.07	0.93
Regular coffee												0.93
Alcohol 0 g/day
Model 1	1.00	Referent	0.96	0.83, 1.11	1.11	0.94, 1.32	0.94	0.82, 1.06	1.07	0.82, 1.39	0.67
Alcohol 0.1–14.9 g/day
Model 1	1.00	Referent	1.14	1.01, 1.28	1.13	1.00, 1.29	1.11	1.00, 1.23	1.05	0.87, 1.27	0.32
Alcohol ≥15 g/day
Model 1	1.00	Referent	0.98	0.83, 1.17	0.86	0.71, 1.03	0.97	0.83, 1.13	0.90	0.72, 1.12	0.61
Decaffeinated coffee												0.93
Alcohol 0 g/day
Model 1	1.00	Referent	1.03	0.92, 1.17	0.97	0.82, 1.14	1.02	0.88, 1.19	1.50	0.92, 2.47	0.69
Alcohol 0.1–14.9 g/day
Model 1	1.00	Referent	0.96	0.87, 1.04	0.98	0.88, 1.10	1.06	0.97, 1.17	1.21	0.83, 1.76	0.14
Alcohol ≥15 g/day
Model 1	1.00	Referent	1.02	0.91, 1.15	1.07	0.98, 1.23	1.02	0.90, 1.15	1.39	0.95, 2.05	0.43

Abbreviations: CI, confidence interval; HR, hazard ratio; BMI, body mass index
^aIncluded men who drink no regular or decaffeinated coffee.
^bModels which were adjusted for age in months, calendar time, smoking (never, past, or current 1–14, 15–24, ≥25 cigarettes/d), BMI (kg/m², <25;25-29.9;30+), total activity metabolic equivalent/week (quintiles), history of diabetes (yes/no), history of hypertension (yes/no), history of hypercholesterolemia (yes/no), history of cardiovascular disease (yes/no), energy intake (kcal/d, quintiles), AHEI score (quintiles), marital status (married, divorced, separated, widowed, or never married), race (White, African-American, Asian American, Other), difficulty of falling into sleep(yes/no), wake up during night(yes/no), not feel rested when wake up (yes/no), medication for lowering cholesterol, lowering blood pressure and sleep medicine (yes/no).