Kaiya H, Sugaya N, Iwasa R, Tochigi M.

Outpatient Clinic for Anxiety Disorders, Akasaka Mental Clinic, Tokyo, Japan.

It was suggested that fatigue is one of characteristics of panic disorder. Fatigue was assessed in 360 patients with panic disorder using the Japanese version of the Multidimensional Fatigue Inventory (MFI-J). The scores for general fatigue and reduced activity were significantly higher in the patients than in the controls. These tendencies were also observed in men when the subject group was differentiated according to sex, but not in women. In contrast, the trend for higher score for physical fatigue was observed only in the female patients. Thus, the present study suggests that the characteristics of fatigue vary with sex in panic disorder.

PMID: 18412848 [PubMed – indexed for MEDLINE]

Sajdyk TJ, Keim SR, Thielen SR, Fitz SD, Shekhar A.

Indiana University Medical Center, Indianapolis, Indiana, USA.

This unit describes a putative animal model for panic disorder. The basic premise is that pharmacological disruption of critical brain regions implicated in the circuitry of anxiety will lead to a condition similar to that of the human disorder. A clinically relevant test, the sodium lactate challenge, is utilized to assess parallels between the human condition and this rat model.

PMID: 18428590 [PubMed – indexed for MEDLINE]

Singareddy R, Uhde TW.

Department of Psychiatry (H073), Penn State College of Medicine, 500 University Drive, PO box 850, Hershey, Pennsylvania 17033, United States.

BACKGROUND: Patients with panic disorder (PD) often complain of sleep disturbances. PD patients have high co-morbid depression and almost 65-70% reports a history of nocturnal panic attacks. It is possible that both nocturnal-sleep panic attacks and depression contribute to sleep disturbances in PD patients. However, the individual and interactive effects of nocturnal-sleep panic attacks and lifetime depression on subjective sleep in PD are unknown. METHODS: The National Institute of Mental Health Panic Disorder Questionnaire (NIMH-PQ) was administered to 773 individuals who met DSM-IV criteria for PD. All of these subjects completed queries related to nocturnal-sleep panic attacks, lifetime depression, difficulty sleeping, and sleep duration. RESULTS: We examined difficulty in sleeping and sleep duration in four subgroups [PD without nocturnal panic attacks or lifetime depression (NP-D-), PD with nocturnal panic attacks (NP+D-), PD with lifetime depression (NP-D+), and PD with both nocturnal panic attacks and lifetime depression (NP+D+)]. Significantly greater proportions of NP+D+ subjects reported difficulty sleeping compared to other three subgroups. In addition, the NP+D+ patients reported significantly decreased subjective sleep durations compared to the other three subgroups. Using </= 5h as a criteria for severe sleep restriction, approximately 20% of the NP+D+ patients, compared to 9.2%, 9.6%, and 2.5% in the NP+D-, NP-D+, NP-D- subgroups, respectively, reported sleeping 5h or less. 8.2% of panic disorder patients reported excessive sleeping per sleeping period. CONCLUSIONS: A high percentage of panic disorder individuals report subjective sleep disturbances. Not surprisingly, an unusually high prevalence of patients with nocturnal panic attacks or depression have sleep problems and 92.3% of patients with both nocturnal panic attacks and depression report striking extremes in sleep duration or insomnia. Thus, nocturnal-sleep panic attacks and depression are independently as well as interactively associated with increased sleep disturbances in panic disorder. Although these findings are expected, they underscore the importance of assessing sleep functions, including over-sleeping, in panic disorder patients.

PMID: 18558437 [PubMed – as supplied by publisher]