OBJECTIVES: To determine the prevalence and 2-year
persistence of subjective sleep complaints in a rural older
population.
DESIGN: A prospective epidemiological study
of an age-stratified random community sample.
SETTING:
The mid-Monongahela Valley, a rural area of Southwestern
Pennsylvania.
PARTICIPANTS: A total of 1050 individuals
with a mean age of 74.4 years (range, 66-97; SD = 5.5); 57.2%
were women.
MEASUREMENTS: Subjective responses to
questions about sleep complaints, classified as "never"
experienced versus "sometimes" or "usually"; these questions
reflected difficulty falling asleep (DFA), sleep continuity
disturbance (SCD), early morning awakening (EMA), and
uncontrollable daytime somnolence (DaSom). Subjects were also
asked about snoring. Frequencies of these complaints were used
to calculate their prevalence; those who remained in the study 2
years later were asked the same questions again to determine the
persistence of sleep complaints. On the first occasions,
subjects were also asked for "usual" estimates of how long they
took to fall asleep, how many times they wakened during the
night, and how many hours of sleep they obtained per night.
RESULTS: With regard to prevalence, 385 (36.7%) subjects
reported DFA, 301 (28.7%) reported SCD, 201 (19.1%) reported EMA,
and 198 individuals (18.9%) reported DaSom. Of those who knew
whether they snored, 334 (40.0%) reported snoring loudly during
sleep. Within the age range of this group, age was not
associated with complaints of insomnia or somnolence; however,
older age was associated with a significantly lower prevalence
of snoring (P < .001). All three insomnia complaints were
significantly more common among women (P < .001). Snoring was
significantly more common among men (P < .005), but there was no
gender difference in DaSom. With regard to subjective estimates,
of those reporting DFA, 49.2% reported that sleep latency
exceeded an hour; of those reporting SCD, 26.2% reported waking
three or more times per night; and of the entire sample, 11.8%
reported 5 hours or less, whereas 12.7% reported 9 to 12 hours,
of sleep per night. Approximately 2 years later, among those who
had reported insomnia previously and participated in the
follow-up wave, the persistence of DFA was 74.9%, that of SCD
68.9%, that of EMA 47.3%, and that of known snoring was 59.6%.
The persistence of DaSom, however, was only 5.7%; only DaSom was
significantly (P = .049) associated with mortality.
CONCLUSIONS: Sleep complaints were common among these older
individuals. Because these data were collected prospectively,
they also provide objective evidence that insomnia is relatively
persistent or chronic among older adults. This finding has
implications for the diagnosis and long-term management of sleep
disorders in older people. Derivation from a random
community-based sample rather than from samples of patients or
volunteers makes these data more generalizable to the general
older population. Finally, these data describe a rural older
populations, a group which, in general, is medically underserved
and understudied.