# Sleep-Disordered Breathing Risk with Comorbid Insomnia Is Associated with Mild Cognitive Impairment
## 3 Results  
Descriptive statistics of the sample and comparisons among the four sleep disorder groups are presented in Table 1. The sample had a mean age of 73.5 \(\pm\) 7.0 years, was 44.8% female, had a mean BMI of 27 \(\pm\) 5 mg/kg\({}^{2}\), 57.8% lacked APOE4 alleles, 92.5% were white, 96.2% were non-Hispanic, and 62.7% had MCI. Among the sample, 72.0% were at low risk for SDB alone, 13.7% were at low risk for SDB with insomnia, 10.1% were at high risk for SDB alone, and 4.1% were at high risk for SDB with insomnia. Several significant differences existed between the four stratified sleep disorder groups (Table 1). Regardless of insomnia status, participants at high risk for SDB were more often male, had greater BMI, and more often reported a history of hypertension or cardiovascular \begin{table}
\begin{tabular}{l c c c c c} \hline \hline  & \multicolumn{4}{c}{**Sleep Disorder Groups**} \\ \cline{2-6}  & **Low Risk for SDB** & \begin{tabular}{c} **Low Risk for** \\ **SDB with** \\ **Insonnia B** \\ \end{tabular} & \begin{tabular}{c} **High Risk for** \\ **SDB Alone C** \\ \end{tabular} & \
\begin{tabular}{c} **High Risk for SDB** \\ **with Insonnia D** \\ \end{tabular} &
\begin{tabular}{c} **Study Sample** \\ **with Insonnia D** \\ \end{tabular} \\ \hline Size, \(n\) (\% study sample) & 1002 (72.0) & 191 (13.7) & 141 (10.1) & 57 (4.1) & 1391 (100) \\ Age, mean years (SD) & 73.5 (6.9) & 72.8 (7.5) & 74.0 (6.9) & 74.1 (7.4) & 73.5 (7.0) \\ Sex, female \% & **47.7 C** & **62.3 A C D** & **7.1** & **28.1 C** & **44.8** \\ BMI, mean mg/kg\({}^{2}\) (SD) & **26.2 (4.5)** & **26.8 (5.2)** & **31.0 (4.8) A B** & **31.8 (5.9) A B** & **27.0 (5.0)** \\ APOE4 alleles & & & & & \\
0, \% & 56.5 & 62.8 & 61.0 & 56.1 & 57.8 \\
1, \% & 35.3 & 31.4 & 30.5 & 42.1 & 34.6 \\
2, \% & 8.2 & 5.8 & 8.5 & 1.8 & 7.6 \\ Race & & & & & \\ White, \% & 92.9 & 92.7 & 91.5 & 86.0 & 92.5 \\ Black or African & 4.3 & 4.2 & 3.5 & 10.5 & 4.5 \\ American, \% & 1.6 & 2.1 & 0.7 & 1.8 & 1.6 \\ Asian, \% & 0.2 & 0.0 & 0.7 & 0.0 & 0.2 \\ American Indian or & & & & & \\ Alaska Native, \% & 0.2 & 0.0 & 0.0 & 0.0 & 0.1 \\ Native Hawaiian or & & & & & \\ Other Pacific Islander, \% & & & & & \\ More than one, \% & **0.6** & **0.5** & **3.5 A** & **1.8** & **0.9** \\ Unknown, \% & 0.2 & 0.5 & 0.0 & 0.0 & 0.2 \\ Ethnicity & & & & & \\ Non-Hispanic or & 96.0 & 95.8 & 96.5 & 100.0 & 96.2 \\ Lating, \% & 3.3 & 4.2 & 2.8 & 0.0 & 3.2 \\ Hispanic or Latino, \% & 0.7 & 0.0 & 0.7 & 0.0 & 0.6 \\ Education, mean years (SD) & 16.0 (2.8) & 16.3 (2.6) & 16.3 (3.0) & 15.9 (2.7) & 16.1 (2.8) \\ Marital status & & & & & \\ Married, \% & **73.2** & **68.6** & **85.8 A B D** & **64.9** & **73.5** \\ Never married, \% & **3.7** & **7.9 C** & **0.7** & **5.3** & **4.0** \\ Divorced, \% & 10.8 & 7.9 & 5.0 & 8.8 & 9.7 \\ Widowed, \% & 12.1 & 14.7 & 7.8 & 19.3 & 12.3 \\ Unknown, \% & 0.3 & 1.0 & 0.7 & 1.8 & 0.5 \\ Hypertension, \% & **40.4** & **44.0** & **95.7 A B** & **86.0 A B** & **48.4** \\ Stroke, \% & **1.0** & **0.5** & **3.5 A** & **0.0** & **1.2** \\ Cardiovascular disease, \% & **61.7** & **69.6** & **95.7 A B** & **93.0 A B** & **67.5** \\ Alcohol abuse, \% & **4.1** & **1.0** & **5.0** & **8.8 B** & **4.0** \\ Smoking, \% & 39.0 & 35.6 & 44.0 & 54.4 & 39.7 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Demographic characteristics of the study population per sleep disorder subgroup. disease. Participants at high risk for SDB without insomnia more often had a history of stroke than those at low risk for SDB without insomnia. Additionally, participants at high risk for SDB with insomnia reported a history of alcohol abuse more often than those at low risk for SDB with insomnia. In logistic regression models of sleep disorder subgroups and MCI, with low risk for SDB alone as the reference group, only high risk for SDB with insomnia was significantly associated with greater odds (OR 3.22, 95% CI 1.57-6.60) of MCI after full covariate adjustment (Table 2).