Measured versus self-reported compliance with doxycycline therapy for chlamydia-associated syndromes: high therapeutic success rates despite poor compliance.
OBJECTIVE
To compare self-reported doxycycline compliance in men and women attending an STD clinic with indications for Chlamydia trachomatis treatment to compliance measured using microprocessor-containing medication vials to count each time and date medication vials were opened. A secondary objective was to correlate outcomes of therapy, as measured by symptom resolution and persistence of chlamydial nucleic acids, with measured doxycycline compliance.


METHODS
Between September 1995 and July 1997, Medication Event Monitoring System (MEMS) caps were used to measure compliance with recommended doxycycline therapy (14 doses over 7 days) in patients treated for presumed C. trachomatis infections. Polymerase chain reaction (PCR) assays for C. trachomatis were performed on urine specimens collected at the time of follow-up evaluation.


RESULTS
Of 221 evaluable participants, although 90% reported taking their medication as directed, only 33 (16%) managed this level of compliance according to data obtained from the MEMS cap. Although 144 (65%) patients took more than 11 of 14 doses over 8 days, 147 (67%) participants had at least one interval of 24 hours or longer between doses in an 8-day period. Of 81 participants with positive C. trachomatis cultures at enrollment, follow-up urine PCR for C. trachomatis was positive in 5 (6%). Medication Event Monitoring System data for four of the five patients with positive PCR tests as follow-up showed each had two or more 24-hour intervals when their medication vials were not opened and three of four had opened their vials less than 11 times.


CONCLUSIONS
This study suggests that few patients take medications as prescribed and that self-report substantially underestimates medication noncompliance. Despite poor compliance, there were few treatment failures.
Bachmann
L H
LH
University of Alabama at Birmingham, 35294-0006, USA.
Stephens
J
J
Richey
C M
CM
Hook
E W
EW
D000293:Adolescent; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000009:adverse effects / Q000627:therapeutic use*; D002690:Chlamydia Infections / Q000188:drug therapy* / Q000382:microbiology; D002692:Chlamydia trachomatis / Q000235:genetics / Q000302:isolation & purification; D004318:Doxycycline / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010349:Patient Compliance; D012646:Self Administration; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents; D004318:Doxycycline