A study of selected elderly psychiatric inpatients admitted for depression suggests that suicidal ideation may initiate a process of smoldering when the patient, family, and professionals interact in such a way as to dampen apparent distress. Suicidal thoughts and mood may be masked by affective or cognitive constriction, camouflaged by anxiety and external agitation, and "tranquilized" by anti-anxiety agents. Depression may go undetected. Distinguishing factors between attempters and ideators are presented.

It is believed that pineal calcification may be age-associated and that the well-demonstrated age-related decline in melatonin biosynthesis may be an expression of an alteration in calcium homeostasis in the pinealocyte. Prior correlations of melatonin to calcium deposition and age were made on the basis of radiological or semiquantitative analysis. In this postmortem study of 33 subjects (age range 3 months to 65 years) calcium deposits measured by atomic absorption spectrometry correlated positively with age in day and night samples (day: r = 0.56, P < 0.05; night: r = 0.818, P < 0.001). Nighttime (2200 h to 0800 h) pineal melatonin content (HPLC fluorometry) was higher than daytime melatonin levels (nighttime 3.80 +/- 0.3 vs. daytime 0.85 +/- 0.4 ng/mg protein). Nighttime calcium levels in the supernatant correlated negatively with melatonin content (r = -0.59, P < 0.05).

Increased pineal calcifications and decreased pineal melatonin biosynthesis, both age related, support the notion of a pineal bio-organic timing mechanism. Decreased calcium ion availability is the single common denominator of diminished β-postreceptor- and α-receptor-stimulating functions in β-receptor potentiation, which is necessary for nocturnal peak melatonin production. A comprehensive framework for the interaction of aging pineal cell mechanisms, calcium flux and melatonin biosynthesis is presented.