Table II.

Partner characteristics by concurrency among sexual partners reported by MSM with recent (acute or early) HIV infection enrolled in the San Diego Primary Infection Resource Consortium (2002-2015).

Partner Characteristics	No concurrent partners (N=311)		≥1 concurrent partner (N=388)		Total (N=699)
Median partnership duration (in months)	0.03	IQR=0.03-0.99	2.95	IQR=0.13-11.77	0.79	IQR=0.03, 6.97
Relationship typea
Main partner	42	16.4	73	23.0	115	20.1
Regular partner	12	4.7	42	13.3	54	9.4
Friend/acquaintance	51	19.9	114	36.0	165	28.8
One-time partner	64	25.0	44	13.9	108	18.9
Anonymous (unknown) partner	81	31.6	39	12.3	120	20.9
Trade partner	6	2.3	5	1.6	11	1.9
HIV serostatus
HIV-negative	105	34.7	174	45.8	279	40.9
HIV-positive	57	18.8	66	17.4	123	18.0
HIV status unknown	141	46.5	140	36.8	281	41.1
Age mixing
>10 years younger than participant	54	17.6	103	27.0	157	22.8
Within 10 years of the participant’s age	187	60.9	233	61.0	420	61.0
>10 years older than participant	66	21.5	46	12.0	112	16.3
Race/ethnicity mixing
Different race/ethnicity than the participant	151	49.2	207	54.3	358	52.0
Same race/ethnicity as the participant	156	50.8	174	45.7	330	48.0
Met partner via the Internet	135	44.1	203	52.3	338	48.7
Any CAI with partner	152	49.8	200	51.6	352	50.8
Illicit drug use during sex with partner
Any illicit drug useb	98	34.2	120	31.2	218	32.4
Marijuana	34	12.5	52	13.6	86	13.1
Amyl nitrite (poppers)	52	18.6	68	17.7	120	18.1
Methamphetamine	55	19.8	61	15.9	116	17.5
Ecstasy	12	4.4	10	2.6	22	3.4
Gamma-hydroxybutyric acid (GHB)	16	5.8	22	5.7	38	5.8
Cocaine	10	3.7	10	2.6	20	3.1
Ketamine	3	1.1	1	0.3	4	0.6
Heroin	0	0.0	0	0.0	0	0.0

Numbers may not sum to column total due to missing data; percentages may not sum to 100 due to rounding or omission of one category for binary variables.

Abbreviations: MSM=men who have sex with men; IQR=interquartile range; CAI=condomless anal intercourse

^aMissing for 126 partners (not collected from 2003 to 2003 during Wave 1).

^bExcludes marijuana.