Why has increased provision of psychiatric treatment not reduced the prevalence of mental disorder?

Psychiatric services in developed countries face a dilemma: despite increased effort and resources directed at mental health problems, measures of psychological distress appear to be worsening. In New Zealand, for example, mental health funding rose from NZD1.1 billion in 2008/2009 to nearly NZD.4 billion in 2015/2016 (New Zealand Ministry of Health data). The number of psychiatrists and psychologists almost doubled from 2005 to 2015. More people than ever are receiving mental health treatment. For example, the Auckland District Health Board reported an increase from around 2000 crisis referrals in 2010 to more than 6000 in 2015. More people are taking psychotropic medications than ever recorded. PHARMAC data in 2015 reveal that 13.7% of all New Zealanders have been dispensed antidepressants and 3.1% antipsychotics. Both rates have increased by more than 50% in the past decade (Ministry of Health Pharmaceutical Collection). Despite all this effort, objective measures of community mental health have not been improving and in most cases are worsening. According to the New Zealand Health Survey, the number of children suffering from psychiatric problems has more than doubled between 2008 and 2013. The percentage of the adult population with high psychological distress (K10 ⩾ 12) has increased from 4.5% in 2011 to 6.8% in 2016. There has been a fourfold increase in people on disability benefits due to a mental illness from 1991 to 2011 (Statistics New Zealand Annual Reports). The suicide rate remains stubbornly high. These data lead to an obvious question: if the treatments we provide are effective, then increasing them should lead to a decrease in measures of community mental disorder rather than the increase we appear to be experiencing. In other words, if our treatments work shouldn’t we have fewer people presenting in crisis, less people on a disability benefit due to mental illness, a reduction in community measures of psychological distress and a decrease in the suicide rate? Given this does not appear to be the case, is doing more of the same a reasonable option? Is training more mental health workers, prescribing more drugs and expanding current services the way to proceed? There are effective treatments in psychiatry which benefit individual patients as shown by randomised controlled trials. But these treatments do not appear to be working at a community level. Is this because they are not being directed at those who will benefit? Have non-illnesses become overdiagnosed and the more severe illnesses, where arguably treatment is more effective, left untreated? Is treatment of poor quality? Are treatments being applied too late? Would things be even worse without the increase in mental health treatments? Regardless, the data require us to pause and reflect on our model of treatment and service delivery. We need to, at the least, consider whether our current mental health systems might be causing unintentional harm in some areas. It is possible that in order to achieve better outcomes, we need to do less, not more. For example, the widespread use of long-term medications has not convincingly been associated with better long-term outcomes for mental disorders (Mulder and Frampton, 2014). Despite access to costly biomedical treatment, something central to recovery appears to be missing in the social fabric of developed countries. It seems likely that factors such as income inequality, discrimination, prejudice, unemployment and strongly materialistic and competitive values may contribute to increased mental distress. In a recent New Zealand study, the level of high psychological distress ranged from 24.3% in the most deprived decile of the population compared to 5.8% overall and 0.8% in the least deprived decile (Foulds et al., 2014). People with low incomes have double the rate of reported loneliness which is associated with psychological distress compared to those with higher incomes (Statistics New Zealand: New Zealand General Social Survey 2014). Why has increased provision of psychiatric treatment not reduced the prevalence of mental disorder?