An alternative spin on the history-as-destiny thesis is that Glasgow is suffering from the effects of deindustrialisation, which often include a decline in health as well as employment.
Some of the rest may be explained by the way official figures tend to exaggerate deindustrialisation: manufacturing firms which used to employ their own accountants or cleaners now hire them from outside firms and so these jobs are reclassified as part of the service sector.