DIGITAL ISCHAEMIA: AN UNUSUAL PRESENTATION OF DYSBARISM

SUMMARY Dysbaric symptoms following ascent from a scuba dive are due to symptomatic nitrogen or air emboli with clear patterns of associated injury. This case report highlights an unusual presentation of dysbaric injury treated successfully with a prostacyclin analogue.     

In the face of fear: anxiety sensitizes defensive responses to fearful faces

Fearful faces readily activate the amygdala. Yet, whether fearful faces evoke fear is unclear. Startle studies show no potentiation of startle by fearful faces, suggesting that such stimuli do not activate defense mechanisms. However, the response to biologically relevant stimuli may be sensitized by anxiety. The present study tested the hypothesis that startle would not be potentiated by fearful faces in a safe context, but that startle would be larger during fearful faces compared to neutral faces in a threat-of-shock context. Subjects viewed fearful and neutral faces in alternating periods of safety and threat of shock. Acoustic startle stimuli were presented in the presence and absence of the faces. Startle was transiently potentiated by fearful faces compared to neutral faces in the threat periods. This suggests that although fearful faces do not prompt behavioral mobilization in an innocuous context, they can do so in an anxiogenic one.     

Impact of Body Mass Index on Left Ventricular Function

Background

Obesity is associated with increased cardiovascular morbidity and mortality. A direct effect of isolated obesity on cardiac function is not well established. The study was designed to determine the direct effect of various grades of isolated obesity on echocardiographic indices of systolic and diastolic left ventricular function.

Methods

Fifty one obese and 25 normal weight, serving personnel without any other pathological condition were studied. Group I (n=25) consisted of subjects with normal weight and body mass index (BMI <25kg/m²), Group II (n=34) of overweight subjects (BMI 25-29.9 kg/m²) and Group III (n=17) of obese subjects (BMI >30 kg/m²). Echocardiographic indices of systolic and diastolic function were obtained and dysfunction was assumed when at least two values differed by ≥ 2 SD from the normal weight group.

Result

Ejection fraction, fractional shortening were increased (p<0.05) in Group II and III. Left ventricular dimensions were increased (p< 0.001) but relative wall thickness was unchanged. Systolic dysfunction was not observed in any of the obese patients. The mitral valve pressure half time (p< 0.01), left atrial diameter (p < 0.01) and the deceleration time were increased (p< 0.01) in obese subjects, while other diastolic variables were unchanged. No difference were found between obesity subgroups. Subclinical diastolic dysfunction was more prevalent among obese subjects. BMI correlated significantly with indices of left ventricular systolic and diastolic function.

Conclusion

Subclinical left ventricular diastolic dysfunction was noted in all grades of obesity which correlates with BMI.Key Words: Obesity, Systolic function, Diastolic function, Echocardiography     

Sexual abuse and the outcome of addiction treatment

The objective of this prospective follow-up study was to examine the effects of sexual abuse on substance use disorder patients' clinical presentation and course in treatment. Consecutive admissions to the MUHC's Addictions Unit were assessed at intake (N=206) and six-month follow-up (n=172). Assessments evaluated socio-demographic and psychiatric characteristics, addiction severity, and physical and/or sexual abuse histories. Upon entering treatment, 23% reported prior sexual abuse with or without physical abuse. Patients with a sexual abuse history had higher rates of psychological problems, stronger family histories of substance use disorders, and more impaired family relationships. At six months, there were no differences between patients with and without sexual abuse histories in their response to treatment, or their utilization of treatment services. The current study failed to show that prior sexual abuse compromised short-term treatment outcomes.     

Diagnosing bipolar disorder in trauma exposed primary care patients

OBJECTIVES: Bipolar disorder (BD) is often under-recognized in non-psychiatric settings, especially in African Americans. The Mood Disorder Questionnaire (MDQ) is a screening instrument proposed to show adequate sensitivity and specificity for bipolar spectrum disorders. The current study is an examination of the usefulness of this instrument in a trauma exposed subgroup of mainly African American patients attending primary care clinics. METHODS: The sample is a part of a larger study exploring traumatic stress exposure and psychopathology. Consenting patients in 3 academically affiliated primary care clinics were asked to complete the MDQ. Ninety percent of the participants were African American. Diagnostic performance was determined in a trauma exposed subgroup by employing the Structured Clinical Interview for DSM-IV (SCID) as a gold standard. RESULTS: Of the total group of 579 participants, 178 (30.7%) screened positive for BD along with 77 (33.7%) of the 228 trauma exposed subjects who were SCID interviewed. Only 13 (27%) of the MDQ positives met SCID criteria for BD and were true positives. The sensitivity was 61.9% and the specificity was 69%, with a positive predictive value of 16.8% and a negative predictive value of 94.7%. CONCLUSIONS: The MDQ was found to have low specificity in a predominately African American group of trauma exposed patients attending primary care.