To characterize
sleep disorders in
methadone maintenance treatment (
MMT) patients, we evaluated sleep quality of 101 non-selective patients from our
MMT clinic in Israel between July, 2003 and July, 2004 by using the self-report questionnaire Pittsburgh Sleep Quality Index (PSQI). Patients' urine tests were analyzed for
methadone metabolite,
opiates,
benzodiazepine,
cocaine, cannabis and
amphetamines. Their urine results for
drug abuse throughout the months prior to filling in the questionnaire and their maintenance
methadone doses were recorded.
Drug abuse was defined by at least one positive urine test.
Methadone serum levels were available in 55 patients, assessed by Gas Chromatography Mass Spectroscopy. The patients' self-reported
chronic pain questionnaires and their diagnosed
psychiatric disorders were analyzed. Out of the 101 study patients, 78.2% were male, 52.5% had
psychiatric disorders, 46.5% reported having
chronic pain and 46.5% had positive urine for
benzodiazepine. The mean daily
methadone dose was 157+/-52.9 mg. The mean PSQI score was 9+/-4.8 (75.2% had scores >5 indicating "poor sleepers"). PSQI scores were higher in patients with positive urine for
benzodiazepine,
chronic pain and
psychiatric disorders and they correlated with years of
opiate abuse before admission to
MMT, and with the
methadone dose (r=0.48, p<0.0005). The latter two also correlated with each other. The PSQI was not correlated with duration in
MMT, gender, age, abuse of
opiates, cannabis or
cocaine. We concluded that
sleep disorders should be evaluated and treated among
MMT patients, particularly in those with
psychiatric disorders,
benzodiazepine abuse,
chronic pain and high
methadone dose.