Background: Several studies have shown that the prevalence of sleep disorders such as sleep apnoea and periodic limb movements in sleep increases significantly with age. The assessment capacity is limited and there is a paucity of knowledge in this field among health professional, hence we hypothesise that these disorders are to a considerable extent under-diagnosed in the elderly, as the symptoms are often conceived of as insomnia.
Material and methods: Using ambulant clinical polysomnography, we investigated 19 patients aged 55 years or above who had been taking hypnotics on a daily basis (5 to 7 days a week) for at least one year.
Results: Among these 19 patients, the prevalence of sleep apnoea (AHI > 10) as well as periodic limb movements in sleep (PLM index > 10) was 42%; 74% had either sleep apnoea, periodic limb movements in sleep, or both.
Interpretation: Seen in relation to the fact that these elderly patients were given hypnotics for insomnia, the prevalence rates of sleep apnoea and periodic limb movements in sleep were high. We suggest that non-pharmacological alternatives should be considered and careful sleep assessment carried out before long-term prescription of hypnotics is instituted.