Depression affects all ages and strata of society

Depression is estimated to affect about 450,000 people in Ireland at any one time and has a lifetime risk of about 10%. The burden of depression is considerable with the World Health Organisation (WHO) predicting that by 2030 it will account for the highest level of disability accorded any physical or mental disorder in the world.

In the majority of cases, depression occurs on the background of adverse psychosocial factors in an individual’s life. The vulnerability to depression however, is greater in those with certain personality traits, including those who are anxious.

Over time, it is believed that these psychological causes can lead to biological disruption in neurotransmitters in our brain that help account for the syndrome of depression. In a minority of cases (10%), depression may have a primary biological basis and occur largely in the absence of major social factors, particularly in those with a strong family history.

Depression affects all ages and all strata of society though it is commonest in those between the ages of 30-40 with a smaller peak in later life. About 10-15% of older Irish adults suffer with depression where it commonly coexists with anxiety (50%). Depression carries with it significant negative health consequences and is associated with an increased risk of heart disease, disability and death. In those who are older, it is also associated with functional and cognitive decline. 

Bereavement, physical disability, chronic pain or stress, insomnia and drug or alcohol misuse use are major risk factors for depression. Significant life changes with maladaptive adjustment reactions can also lead to depression. 


Loneliness (or the perception of poor social contact) is also a major risk factor which has become the focus of much research in recent years. It particularly affects those at the younger and older end of the age spectrum, and is associated with being single, living alone, physical ill health, social isolation and a reduction in both the quality of and time spent in social interactions.

While having good social contact in a general sense may prevent ‘social loneliness’ it may not prevent ‘emotional loneliness’ (the perception of the need for closer or more intimate relationships) which is also detrimental. Several studies show that loneliness is an independent risk factor for adverse health behaviour and outcomes even after adjusting for social isolation. Evidence also suggests a negative effect at a biological level, including alteration of cortisol stress response, the immune system and brain changes on neuroimaging. In fact, loneliness is considered a health issue that appears to be as damaging as smoking 15 cigarettes a day. 

The first important but often delayed step lies with acknowledging that a problem exists and seeking help. Depression is usually diagnosed when five or more core symptoms are present on most days over a two-week period. 

These include low mood, excessive or too little sleep, lack of pleasure for most activities, poor concentration, indecisiveness, loss of appetite, lethargy, a feeling of worthlessness and thoughts of death or self-harm. 

However, it may present atypically especially in older adults. In addition, a ‘subthreshold’ or ‘subsyndromal depression’ may exist when the number, duration or quality of symptoms is insufficient to meet a formal diagnosis, but is more common and affects up 18% of Irish adults aged over 50.

For major biologic depression, first line treatment is with anti-depressants which have a success rate of about 70% and appear to work by increasing neurotransmitters such as serotonin and noradrenaline in the brain. 

In those with a reactive depression on a background of psychosocial stressors, a big emphasis should be on addressing relevant precipitating factors with interventions such as anxiety and stress management, drug /alcohol or relationship counselling, family therapy, interpersonal skill training and goal setting. 

The approach of cognitive behavioural therapy is effective, which aims to change the way you feel by changing the way you think. In addition, in a reactive depression, anti-depressants appear to help and can also reduce anxiety. 

Overall, about 50% with depression will recover within the first six months of treatment while approximately 10% have a more chronic course over years.

In general, try and keep in touch with friends and family as socialising may improve your mood and allow you to talk to someone when you are low. 

Sticking to a routine especially when it comes to meal and bedtimes may help to maintain your sleep pattern and nutrition. 

Try and cut down on alcohol which can become a crutch for comorbid anxiety. Consider doing regular exercise which can improve mood in mild to moderate depression as has been shown in several studies.

Finally, remember, it is not so much what we are confronted with in life but the way in which we approach and deal with it that determines how it affects us. Help is available out there so don’t be afraid to talk to others or go to your GP for advice.


Dr Kevin McCarroll is a consultant physician in geriatric medicine in St James’s Hospital, Dublin.