Does CPAP lead to change in BMI?

STUDY OBJECTIVES

Obesity is an important risk factor for obstructive sleep apnea syndrome (OSAS), and weight loss can reduce apnea severity or even lead to resolution in some patients. Effective CPAP therapy may lead to weight loss by any of several proposed mechanisms, including, but not limited to, increased physical activity and increased responsiveness to leptin. This retrospective study sought to determine whether subjects who adhered to prescribed CPAP treatment for OSAS would lose weight, or gain less weight than control subjects who were either untreated or did not adhere to prescribed CPAP treatment.

METHODS

BMI was determined at the time of diagnosis and at followup approximately 1 year (10-14 months) later. Subjects who used CPAP > or = 4 h per night and > or = 70% of nights were considered treatment subjects. Control subjects used no treatment for OSAS or used CPAP < 4 hours per night or < 70% of nights for 1 year.

RESULTS

BMI of treatment and control subjects did not significantly differ (p = 0.3157). BMI increased with 1 year of CPAP use in women but not men (p = 0.0228) and in non-obese subjects (p = 0.0443). BMI did not significantly decrease in any group treated with CPAP.

CONCLUSIONS

CPAP was associated with weight gain in some; none lost weight. CPAP may affect weight in ways not measured here. Physicians should stress an active weight loss plan and not assume CPAP alone will lead to weight loss. A larger, prospective study may help clarify these findings.

A single question as a sleepiness screening tool

STUDY OBJECTIVES

A single subjective question may be an effective screening tool for excessive daytime sleepiness. This study sought to determine whether the following single question about sleepiness can measure subjective sleepiness comparably to the Epworth Sleepiness Scale (ESS): "Please measure your sleepiness on a typical day: (0 = none, 10 is highest)." The relationship between this question and objective sleepiness as measured by the MSLT was also evaluated.

METHODS

303 subjects completed a sleep questionnaire, MSLT, and ESS within 2 months. ROC (receiver-operator characteristic) curves and contingency tables using Fisher's exact test were made using GraphPad Prism software.

RESULTS

ESS and SS scores showed a significant association at all SS score cut-points. ESS and MSL showed significant associations only at ESS scores 11, 12, and 18. SS scores were significantly related to the MSL only in non-sleep apneics at SS scores 2, 5, 6, and 8, and in sleep apneics at SS score 9. ROC analysis showed the SS could distinguish subjects with an ESS > or = 11 from those with an ESS < 11 (area = 0.71, p < 0.0001).

CONCLUSIONS

Neither the SS nor the ESS substitutes for the MSLT, which measures objective sleepiness and is not an appropriate screening tool. SS scores < or = 2 and > or = 9 reliably predict normal and abnormal ESS scores respectively. Since the ESS is not commonly used in non-sleep specialized practices, the SS may serve as a useful screening tool for patients with disorders of sleepiness.

Sleep-isolated trichotillomania: a survey of dermatologists

STUDY OBJECTIVES

To determine whether sleep-isolated trichotillomania has been recognized or suspected by dermatologists.

METHODS

Eight-hundred and seven practicing dermatologists in the Midwest were identified through the American Academy of Dermatologists website database. A 10-question multiple-choice survey regarding trichotillomania was mailed to each. Responses were anonymously returned by fax.

RESULTS

A total of 107 (13%) of the 807 dermatologists surveyed responded. Twelve (11%) reported having seen patients with trichotillomania that occurred solely during sleep. In cases of unexplained hair loss, 21(20%) suspected hair-pulling occurred only in sleep. Seventy-six subjects (71%) said they had seen patients with unexplained hair loss; 67 (88%) of those respondents said they would ask those patients if they pull their hair. Only 16 (24%) said they would ask patients who deny hair pulling while awake if they pull their hair during sleep. Twenty (19%) said they ask patients diagnosed with trichotillomania if hair pulling also occurs in sleep.

CONCLUSIONS

Although sleep-isolated trichotillomania has only recently been reported, some dermatologists report having recognized this entity in their own practices. When dermatologists see patients with unexplained hair loss, only a small percentage consider trichotillomania isolated to sleep. Increased physician awareness of this disorder may allow diagnosis and treatment of many patients.