Of 164 identified patients, 111 took part in the study:81 males (mean age = 67.3 years, standard deviation [SD] = 8.8), and 23 females (mean age = 67.3 years, SD = 11.5).
The criteria for full PTSD was met by 36/111participants. If those who were invited but did not take part were assumed not to have PTSD, the prevalence would be 36/164 (22%). There was no significant difference in prevalence of full PTSD for sex (27/88 males; 9/23 females, P = 0.46) or for participants having multiple or single events. None of the patients diagnosed with PTSD had a prior diagnosis of PTSD. PTSD prevalence was not related to time since the relevant myocardial infarction (<5 years, 9/32 patients; 5–10 years, 11/37 patients; >10 years, 16/42 patients; P = 0.60). Furthermore, symptom severity of all patients did not vary with time. There was no significant difference in total post-traumatic symptom severity score, or subscale scores: hyperarousal, intrusive thoughts, avoidance, and time since the myocardial infarction.
Full PTSD was associated with higher psychological morbidity: 32/36 were ‘GHQ cases’, compared to 35/50 with partial PTSD and 6/23 with no PTSD. For GHQ domains all showed significantly worse scores. Median GHQ scores (interquartile range) for those with PTSD versus those without were: somatisation 8.5 (5.0–13.0) versus 5.0 (2.5–8.5), P<0.001; anxiety 10.5 (6.0–14.0) versus 4.0 (1.5–9.5), P<0.001; social dysfunction 9.5 (8.0–14.0) versus 8 (7.0–10.0), P = 0.001; depression 3.5 (0.2–10.7) versus 0.0 (0–2.0), P = 0.004.
How this fits in
Post-traumatic stress disorder (PTSD) is an under-diagnosed cause of psychological distress in primary care. PTSD relating to myocardial infarction has not been studied in a primary care setting. This study shows that PTSD affects up to one-third of patients after myocardial infarction, with symptoms persisting for many years. PTSD is associated with poor general health. As effective treatments are available, the possibility of PTSD should be considered at post myocardial infarction reviews.
Two-year follow-up data were available for 92/111 participants. There was no difference in prescriptions for secondary prevention of coronary heart disease for participants with or without PTSD ().Participants with PTSD had higher compliance with β-blocker treatment () but there was no difference for compliance with anti-platelet, lipid-lowering, or angiotensin-converting enzyme (ACE)-inhibitor treatment.
Prescription of drugs for secondary prevention of myocardial infarction for participants with no PTSD, partial PTSD, and full PTSD.
Compliance with treatment and PTSD status.
Finally, there was no difference between participants with and without PTSD in attendance at annual review of cardiac risk, or recordings of blood pressure, lipid and glucose, smoking status, or exercise grading. Alcohol consumption was similar between groups, and excessive consumption was present in 1/28 of patients with PTSD and 5/63 without PTSD (P = 0.66).