Anuja N. Roy

Date of Graduation

2007

Document Type

Dissertation/Thesis

Abstract

It is estimated that almost one-thirds of the patients in primary care settings experience some form of insomnia. Co-morbid insomnia accounts for almost 75% of such cases and, is considered to be a symptom (rather than a stand-alone disorder) that remits with treatment of the underlying medical or psychiatric disorder. In Phase I, this study examined if there was any incremental impact of co-morbid insomnia (after controlling for confounding covariates) on health-related quality of life (as measured by the Medical Outcomes Study 36 Item Short-Form Health Survey, i.e., SF-36, and the EuroQoL 5D, i.e., EQ-5D) compared to similar patients without insomnia across five disease groups i.e., cardiovascular, diabetes, gastrointestinal, musculoskeletal, and obstructive airways diseases. The study also estimated ‘utilities’ (cardinal numbers reflecting health-related quality of life experienced) attached to various health states in insomnia (using the EQ-5D), by means of a self-administered mailed survey of patients visiting the Clark K. Sleeth Family Medicine Center, West Virginia University, Morgantown, WV. In Phase II, the study estimated the minimum quantum of improvements in sleep problems (as measured by the Insomnia Severity Index, i.e., ISI), sleep quality (as measured by the Pittsburgh Sleep Quality Index, i.e., PSQI), and HRQL (as measured by SF-36) considered ‘meaningful’ by patients suffering from insomnia, and examined stated preferences (in the form of willingness to pay) for various attributes of symptom relief offered by hypnotic drugs. Phase II employed, one-on-one discussions of patients, and filling of paper-and-pencil format discrete choice experiment questionnaire (DCE), in the presence of the researcher. As an extension arm of Phase II a mailed survey of the DCE questionnaire was also carried out. Phase I Results: Based on an overall response rate of 46.58% (N=1,020) it was seen that average scores (associated with insomnia) in HRQL domains compared with the no-insomnia group after controlling for socio-demographic characteristics, health habits, BMI, number of medical conditions, and the presence of depressive symptoms were significantly lower for all domains across the five disease groups. Analysis of EQ-5D scores after controlling for all relevant covariates, showed significantly lower utilities in the insomnia group when compared to the no-insomnia group in all disease groups. Phase II Results: Based on discussions of each of 45 patients (identified as having ‘insomnia’ from Phase I and invited to participate in discussions involving one-on-one interactions with three other patients) there seem to be certain quanta of changes on the ISI, PSQI, and SF-36 that insomnia patients consider ‘meaningful’. However, deterioration and improvements did not seem to be viewed in a similar manner. Again, willingness to pay (WTP) estimates obtained by means of a DCE administered to 45 patients, who were invited for discussions (and from another 82 patients through a mailed survey) revealed that patients have different preferences for different attributes of treatment-induced symptom relief in insomnia.

Download

Share

COinS