Polysomnographic and psychometric correlates of napping in primary insomnia patients

Abstract

Introduction: This study aims to evaluate napping in patients with insomnia compared with two control groups and to investigate the relationships between psychometric measures and napping habitude.

Methods: Sixty-eight adult patients with chronic primary insomnia were enrolled; 27 men and 41 women, mean age 53.6 ± 13. All patients underwent 24 h ambulatory polysomnography (A-PSG). Prevalence of napping behavior in Insomnia Patients (I-group) was compared with Obstructive Sleep Apnea Syndrome (OSAS) patients (OSAS-group) and epilepsy patients (Ep-group). Patients were evaluated with Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS) and Berlin Questionnaire. Psychometric evaluation included Self-Administered Anxiety Scale (SAS #54), Beck Depression Inventory (BDI), Maudsley’s Obsessive Compulsive Inventory (MOCI), Snaith-Hamilton Pleasure Scale (SHAPS), and Eating Attitude Test (EAT-26).

Results: No significant differences resulted in prevalence and duration of naps in the three groups. In the comparison between nappers (N+, subject with at least one nap in A-PSG) and non-nappers (N-, subject with no naps in A-PSG) we observed significant differences in PSQI scores (N+ = 14.1 ± 2.7; N− =11.9 ± 3.3; Whitney U-test = 341.0; p = 0.004) and in EAT score (N+ = 9.8 ± 9.7; N− = 4.4 ± 5.6; Whitney U-test = 313.5, p = 0.0.14); no significant differences were measured in other psychometric parameters and in sleep macrostructural indexes.

Conclusions: Our data are in accordance with previous findings outlining that N + insomniacs have higher PSQI scores than N-. Our results do not confirm the suggested association between napping and depressive or obsessive-compulsive symptoms. Conversely, we found a statistically significant difference (p = 0.0014) in EAT scores in N + and N-. Hyperarousal and REM sleep instability in insomniac patients may create an unbalance of the neuroendocrine hypothalamic regulation leading to an appetite alteration.

Keywords:

• Insomnia
• nap
• napping
• polysomnography
• psychometric scales
• sleep

Acknowledgement

We would like to thank patients who participated in this study and two anonymous reviewers for their useful suggestions.

Ethics approval

The study was designed in accord with the Helsinki Declaration of 1975 and approved by the local Ethics Committee. All patients were fully informed and gave a written consent to participate.

Disclosure statement

Authors declare no sources of funding and no financial support for this study. All authors have seen and approved the manuscript.

Additional information

Notes on contributors

Marianna Mazza

Marianna Mazza, MD, PhD, is a psychiatrist and psychotherapist, Institute of Psychiatry and Clinical Psychology, Department of Geriatrics, Neuroscience and Orthopedics, Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, Roma, Italia.

Leonardo Lapenta

Leonardo Lapenta, MD, is a neurologist, Institute of Neurology, Department of Geriatrics, Neuroscience and Orthopedics, Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, Roma, Italia.

Anna Losurdo

Anna Losurdo, MD, is a neurologist, Institute of Neurology, Department of Geriatrics, Neuroscience and Orthopedics, Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, Roma, Italia.

Giuseppe Marano

Giuseppe Marano, MD, is a licensed professional counselor, Institute of Psychiatry and Clinical Psychology, Department of Geriatrics, Neuroscience and Orthopedics, Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, Roma, Italia.

Elisa Testani

Elisa Testani, MD, is a neurologist, Institute of Neurology, Department of Geriatrics, Neuroscience and Orthopedics, Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, Roma, Italia.

Luigi Janiri

Luigi Janiri, MD, is a psychiatrist and psychoterapist, Institute of Psychiatry and Clinical Psychology, Department of Geriatrics, Neuroscience and Orthopedics, Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, Roma, Italia.

Salvatore Mazza

Salvatore Mazza, MD, is a neurologist, Institute of Neurology, Department of Geriatrics, Neuroscience and Orthopedics, Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, Roma, Italia.

Giacomo Della Marca

Giacomo Della Marca, MD, PhD, is a neurologist, Institute of Neurology, Department of Geriatrics, Neuroscience and Orthopedics, Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, Roma, Italia.