Risk Management on Pre-Exposure Prophylaxis Adherence of Men Who Have Sex with Multiple Men: A Multicenter Prospective Cohort Study

Figures & data

Table 1 Scoring of PrEP Adherence Protection Motivation Factors

Factor		Variable	Value Assignment
Threat assessment	Severity	What do you know about the severity of AIDS?	1 = Not serious at all, 2 = Not too serious, 3 = Somewhat serious, 4 = Serious, 5 = Very serious
		What do you know about the HIV infection rate among MSM around you?	1 = Very low, 2 = Low, 3 = Average, 4 = High, 5 = Very high
	Susceptibility	How much of a threat do you consider AIDS to be for you and your family?	1 = Very small, 2 = Small, 3 = Average, 4 = Large, 5 = Very large
	External reward	What is your male partner’s attitude towards you taking PrEP drugs?	5 = Very supportive, 4 = Moderately supportive; 3 = Not very supportive 2 = Comparatively opposed; 1 = Fully opposed
	Internal reward	I think it is inconvenient to take the medication	5 = Not at all, 4 = Agree a little, 3 = Agree to some extent, 2 = Mostly agree, 1 = Always
		I find it very troublesome to take medication
Response assessment	Self-efficacy	How do you feel about the prophylaxis: when HIV preventive drugs are not immediately available?	1 = Not confident at all, 2 = Not confident, 3 = Comparatively confident, 4 = Very confident, 5 = Completely confident
		When you had (recently) been drinking or using other drugs?
		When your sex partner is upset about the medication?
		When you feel medications’ side effects?
		When the burden of HIV is too much?
		When you think that your sex partners will not approve of your use of HIV preventive drugs?
		When you think the risk of AIDS is very low?
		When you have used other protective measures such as condoms?
	Response benefit	I think drugs make me safer and prevent AIDS	1 = Do not agree at all, 2 = Agree a little, 3 = Agree to some extent, 4 = Mostly agree, 5 = Always
	Response cost	I am worried that the medication will not work	5 = Not at all, 4 = A little, 3 = Somewhat, 2 = Mostly, 1 = Always
		I worry about the side effects of the medication
		I worry about homosexual partners learning that I am taking medication
		I worry that others will discriminate me when they learn I am on medication
		I think the doctors here discriminate me

Abbreviation: PrEP, pre-exposure prophylaxis.

Figure 1 Flow chart of participants’ enrollment.

Table 2 HIV Antibody Positivity Conversion Rate in MSMM

Characteristics	Total (n=496)		HIV-Positive (n=47)		HIV-Negative (n=449)		χ^2	p-value
	n	%	n	%	n	%
Adherence
Good Adherence	299	9.48	12	4.01	287	95.99	26.1865	<0.0001
Poor Adherence	197	90.52	35	17.77	162	82.23
Medication Mode
Daily PrEP group	213	42.94	23	10.80	190	89.20	0.761	0.383
On-demand PrEP group	283	57.06	24	8.84	259	91.52

Note: Bold value indicates statistical significance with p < 0.05.

Abbreviations: HIV, human immunodeficiency virus; MSMM, men who have sex with multiple men.

Table 3 Characteristics of Men Who Have Sex with Multiple Men (MSMM) and Univariate Analysis

Characteristics	Total (n=496)		Good Adherence (n=299)		Poor Adherence (n=197)		χ^2	p-value
	n	%	n	%	n	%
Medication mode
Daily PrEP group	213	42.94	115	53.99	98	46.01	6.1721	0.0130
On-demand PrEP group	283	57.06	184	65.02	99	34.98
Social demographic characteristics
Age, years
18–30	279	56.25	160	57.35	119	42.65	2.2938	0.1299
≥31	217	43.75	139	64.06	78	35.94
Area
Urban	369	74.40	223	60.43	146	39.57	0.0138	0.9065
Rural	127	25.60	76	59.84	51	40.16
Ethnic groups
Han nationality	442	89.11	262	59.28	180	40.72	1.7169	0.1901
Other ethnic minorities	54	10.89	37	68.52	17	31.48
Educational level^#
Junior high or below	60	12.12	36	60.00	24	40.00	2.8615	0.2391*
Senior high	139	28.08	76	54.68	63	45.32
College or above	296	59.80	187	63.18	109	36.82
Employment status^#
Employed	393	79.39	240	61.07	153	38.93	6.2405	0.0441
Students at school	46	9.29	32	69.57	14	30.43
Retired or unemployed	56	11.31	26	46.43	30	53.57
Marital status
Unmarried	354	71.37	214	60.45	140	39.55	0.0719	0.9647
Married	88	17.74	52	59.09	36	40.91
Divorce or widowhood	54	10.89	33	61.11	21	38.89
Personal monthly income (RMB)
≤3000	250	51.12	153	61.20	97	38.80	1.0400	0.5945
3001–5000	180	36.81	110	61.11	70	38.89
≥5001	59	12.07	32	54.24	27	45.76
Sexual behavior characteristics
The sex position during anal sexual intercourse with men^#
Only doing insertive anal sex “1”	114	23.03	65	57.02	49	42.98	4.7163	0.3177
Both but “1” mainly	131	26.46	77	58.78	54	41.22
Both equally	131	26.46	89	67.94	42	32.06
Both but “0” mainly	76	15.35	42	55.26	34	44.74
Only doing receptive anal sex “0”	43	8.69	25	58.14	18	41.86
Temporary male sexual partners in the past 6 months^#
0	67	13.65	37	55.22	30	44.78	1.5970	0.4500
1	150	30.55	96	64.00	54	36.00
≥2	274	55.80	164	59.85	110	40.15
Female sexual partners in the past 6 months^#
0	411	84.57	250	60.83	161	39.17	1.9623	0.3749
1	69	14.20	43	62.32	26	37.68
≥2	6	1.23	2	33.33	4	66.67
Frequency of condom use when having anal sex with men^#
Always	282	58.51	183	64.89	99	35.11	7.5582	0.0228
Occasionally	172	35.68	91	52.91	81	47.09
Never	28	5.81	14	50.00	14	50.00
Frequency of Internet-seeking sexual partners in the past 6 months^#
Often	47	9.49	30	63.83	17	36.17	4.4665	0.1072
Sometimes or occasionally	348	70.30	217	62.36	131	37.64
Never	100	20.20	51	51.00	49	49.00
Whether a commercial sexual service in the past 6 months
Yes	38	7.66	24	63.16	14	36.84	0.1421	0.7062
No	458	92.34	275	60.04	183	39.96
Diagnosed with STD in the past 6 months^#
Yes	54	10.95	27	50.00	27	50.00	2.6567	0.1031
No	439	89.05	270	61.50	169	38.50
HIV knowledge and testing and counseling
HIV voluntary testing
Yes	409	82.46	252	61.61	157	38.39	1.7264	0.1889
No	87	17.54	47	54.02	40	45.98
HIV voluntary counseling^#
Yes	326	65.99	203	62.27	123	37.73	1.8456	0.1743
No	168	34.01	94	55.95	74	44.05
HIV knowledge score
≤11	231	46.57	124	53.68	107	46.32	7.8723	0.0050
>11	265	53.43	175	66.04	90	33.96
Substance use
Frequency of alcohol use in the last month
Daily	17	3.43	9	52.94	8	47.06	1.7413	0.7832
At least 3 times/week	48	9.68	29	60.42	19	39.58
At least 1 time/week	80	16.13	44	55.00	36	45.00
Less than 1 time/week	201	40.52	123	61.19	78	38.81
Never	150	30.24	94	62.67	56	37.33
Whether illicit drugs (ecstasy, methamphetamine, k powder (ketamine), etc) used in the last half year^#
No	472	96.72	285	60.38	187	39.62	1.7811	0.1820
Yes	16	3.28	7	43.75	9	56.25

Notes: *Rank sum test, and χ² test was used for the rest. ^#Indicates loss of data, the average missing rates of variables were <0.9%. Bold values indicate statistical significance with p < 0.05.

Table 4 Comparison of Protection Motivation Scores in MSMM from Different Adherence Groups

Protection Motivation Factors	Good Adherence ≥ 0.6 (n=299)	Poor Adherence<0.6 (n=197)	t	p-value
	Mean ± SD	Mean ± SD
Threat assessment	2.15±0.59	2.06±0.47	2.02	0.0443
Severity	1.78±0.59	1.78±0.63	−0.03	0.9728
Susceptibility	1.96±1.28	1.65±0.93	3.10	0.0021
External reward	2.49±1.02	2.54±1.03	−0.51	0.6071
Internal reward	2.39±1.07	2.26±1.02	1.37	0.1709
Response assessment	2.81±0.62	2.74±0.62	1.24	0.2162
Self-efficacy	2.87±0.75	2.79±0.75	1.18	0.2391
Response benefit	3.14±1.32	3.18±1.39	−0.30	0.7639
Response cost	2.43±0.73	2.26±0.76	2.45	0.0147

Notes: Analysis using a t-test of two independent samples. Bold values indicate statistical significance with p < 0.05.

Abbreviations: MSMM, men who have sex with multiple men; SD, standard deviation.

Table 5 Multivariate Logistic Stepwise Regression Analysis of PrEP Adherence Among MSMM

Model	Independent Variable	p-value	OR	95% CI for OR
				Lower	Upper
Model 1
	Employment status
	Employed (reference)
	Students at school	0.042	1.837	1.024	3.299
	Retired or unemployed	0.180	0.629	0.319	1.240
	Medication mode
	Daily PrEP group (reference)
	On-demand PrEP group	0.038	0.670	0.458	0.978
	Frequency of condom use when having anal sex with men
	Always (reference)
	Occasionally	0.017	1.621	1.091	2.409
	Never	0.257	1.591	0.713	3.550
	HIV knowledge score
	≤11 (reference)
	>11	0.004	0.565	0.385	0.828
Model 2
	Threat assessment score	0.036	0.685	0.481	0.976
	Medication Mode
	Daily PrEP group (reference)
	On-demand PrEP group	0.049	0.683	0.466	0.999
	Frequency of condom use when having anal sex with men
	Always (reference)
	Occasionally	0.019	1.607	1.080	2.391
	Never	0.183	1.736	0.770	3.911
	HIV knowledge score
	≤11 (reference)
	>11	0.009	0.602	0.411	0.880
Model 3
	Susceptibility score	0.007	0.785	0.659	0.936
	Response cost score	0.001	0.639	0.491	0.832
	Frequency of condom use when having anal sex with men
	Always (reference)
	Occasionally	0.012	1.673	1.121	2.498
	Never	0.274	1.567	0.701	3.504
	HIV knowledge score
	≤11 (reference)
	>11	0.034	0.659	0.447	0.969

Note: Bold values indicate statistical significance with p < 0.05.

Abbreviations: CI, confidence interval; OR, odds ratio; MSMM, men who have sex with multiple men; PrEP, pre-exposure prophylaxis.