TABLE 3

The effect of concomitant centrally acting drugs/opioids on the prevalence of sleep apnoea compared to sole opioid use

Variable	n	Apnoea–hypopnoea index ≥5
Variable	n	OR (95% CI)	p-value
Age years	204	1.06 (1.03–1.09)	<0.001***
Male sex	84	1.78 (0.92–3.46)	0.085
Body mass index kg·m⁻²	204	1.08 (1.03–1.14)	0.004*
MME mg per day	202	2.10 (1.14–3.87)	0.017*
Cannabis use	15	1.25 (0.37–4.21)	0.722
Opioids+benzodiazepines	31	0.31 (0.12–0.80)	0.015*
Opioids+zopiclone	12	0.64 (0.17–2.46)	0.516
Opioids+antidepressants	51	0.97 (0.47–2.00)	0.929
Opioids+gabapentinoids	80	0.91 (0.46–1.79)	0.787
Opioids+muscle relaxants	14	0.98 (0.26–3.68)	0.971

Multivariable logistic regression was used for the apnoea–hypopnoea index, adjusted for age (years), sex, body mass index (kg·m⁻²), MME (mg per day), cannabis and use of ≥2 centrally acting drugs. Use of centrally acting drugs, sex, and cannabis use were all dichotomously coded. Age, body mass index, and MME are continuous variables. AHI is also dichotomously coded: 0: score <5; 1: score ≥5. MME was log₁₀ (x+1) transformed. MME: morphine milligram equivalent; AHI: apnoea–hypopnoea index; OR: odds ratio; CI: confidence interval. *: <0.05; ***: <0.001.