This month we are going meta — meta-analysis, that is. Meta-analyses are powerful statistical studies that combine the results of multiple studies in order to be more confident in the results and effect sizes, and can help resolve uncertainty when studies have conflicting results. Although pooling data from multiple studies doesn’t come without problems and biases, convincing results from a well-constructed meta-analysis based on high quality standardized research is the closest we can hope to get to true factuality.

THE BEST

BEST: More good moods in later years means lower mortality risk

A rather rigorous meta-analysis examined the relationship between how many positive moods an individual feels (positive affect) and the likelihood of death (mortality risk) in older adults, aged 55 years and older.

Both research that was poorly controlled for, and research that more stringently assessed contributions from other variables (such as medical, psychological, and social factors), indicated that older adults with higher levels of good moods had lower risk of death than those with lower levels of positive affect, calculated as 75% and 85% lower mortality risk respectively. Basically, this suggests that fostering a good mood boosting lifestyle and habits can go a long way to living a longer life.

BEST: CBT top treatment for PTSD in youth

A large meta-analysis (135 studies, 150 treatment conditions and 9562 participants) quantified the effects of different psychological treatments of post-traumatic stress disorder (PTSD) symptoms in both children and adolescents.

The largest effect sizes were found for cognitive behavioral therapy (CBT), especially when individual treatment is conducted along with parents. This marks CBT as being a highly effective and preferred treatment for dealing with trauma symptoms in youth populations.

BEST: Online mindfulness-based interventions improve mental health and reduce stress

While many meta-analyses have investigated the effectiveness of face-to-face mindfulness based interventions (MBIs) the current meta-analysis is the first to assess the effectiveness of online MBIs.

Based on 15 randomised controlled trials, results showed that online MBIs have a small but significant beneficial impact on depression, anxiety, well-being and of course, mindfulness. However, the largest and more moderate effect was found for stress reduction, where guided online MBIs with many intervention sessions had an increased advantage over unguided online MBIs or fewer intervention sessions.

BEST: Psychotherapy alone suggested over combined therapy for long-term major depression treatment

The present meta-analysis examined to what extent combined pharmacotherapy with psychotherapy results in a different long-term response to treatment compared to psychotherapy or pharmacotherapy alone (i.e. monotherapy) for adults with major depression. Assessment was further subdivided into effectiveness in the initial acute phase of treatment, and effectiveness in the maintenance phase of treatment, where preventing relapse and recurrence of depression is the primary objective.

In acute phase treatment, combined psychotherapy with antidepressants outperformed antidepressants alone and was equal to psychotherapy alone at six months or longer post-randomization. For the maintenance treatment, combined maintenance psychotherapy with antidepressants resulted in better-sustained treatment response compared to antidepressants. The authors suggest that psychotherapy is an adequate drug-free alternative for combined treatment in the acute phase as it is as effective as combined treatment in the long-term.

BEST: High-frequency, not low-frequency magnetic brain stimulation, improves major psychiatric disorders

A systematic review assessed the effects of deep transcranial magnetic stimulation (dTMS) as a non-invasive brain stimulation method for the treatment of major psychotic disorders.

From the 13 studies that met inclusion criteria it was found that low-frequency DTMS (1-3 sessions) had little effect on cognitive functioning in healthy participants. The most consistent cognitive and clinical improvements were reported in the short-term after 20 daily sessions of high-frequency DTMS in studies with major depression patients, and to a lesser extent, in studies with schizophrenia patients. However, the authors note that it is time for new randomised, sham-controlled trials as this conclusion is based on data from mostly uncontrolled, open-label studies with patients receiving concurrent antidepressants or antipsychotics which could confound results.

THE WORST

WORST: Parental arguments, control and role-reversal raise risk of adult alcoholism

The present study examined the links between the development of drinking problems in later life and 23 types of childhood risk factors in a total sample of 1,008 online participants living in Poland and Germany.

Using stringent statistical cutoffs, only three of the 23 risk factors displayed a significant association with problematic alcohol use in adulthood: regular arguments between parents, maternal control and maternal role reversal (i.e where a child sacrifices their needs in order to adapt and take care of instrumental or emotional needs of a parent). While these factors may also be related to emotional or physical abuse, which are known strong predictors of future alcoholism, the results highlight that attention should also be paid to more subtle symptoms of a disturbed parent-child relationship, such as maternal parentification or control.

WORST: Empathy deficits in schizophrenia confirmed

The discussed meta-analysis is the first to assess reported deficits in the emotional response to the experiences or emotional states of others in schizophrenia patients. Known as affective empathy, this is important for fostering social connections and maintaining relationships. 37 records met inclusion criteria, totaling 1,468 people with schizophrenia disorders and 1,247 healthy controls.

The results confirm a significant deficit in affective empathy for people with schizophrenia disorders, the effect being considered medium in magnitude. Interestingly, the type of affective empathy measuring tool used was a moderator of the effect size, where self-report measures produced much smaller effects than performance-based tests. This led authors to suggest that individuals with schizophrenia perceive themselves to be more empathic than their skills demonstrate in performance-based assessments. More rigorous investigation of empathy measurement techniques is therefore important to furthering research.

WORST: Higher odds for depressive disorder following disasters and military deployment

While the relationship between PTSD and disasters/military deployment is well-established, less is known about the risk of major depression. The present study addressed this gap in knowledge by pooling data from 23 epidemiological studies that assess the link between disasters/combat experience with risk of depression.

The odds ratios (OR, i.e. the chance of having depression after a disaster/combat, compared to the chance of having depression with no disaster/combat) were significantly elevated for natural disasters (OR=2.28), technological disaster (OR=1.44), terrorist acts (OR=1.80) and military combat (OR=1.60). The authors advocate future research exploring whether psychological trauma or bereavement are causal routes to disaster-related depression.

WORST: A third of Parkinson’s patients suffer from anxiety

A meta-analysis of data from 45 research articles was performed to explore the widely varying prevalence rates for anxiety disorders in Parkinson’s disease in previous research (from 6-55%).

The researchers found that 31% of subjects with Parkinson’s disease also suffered from anxiety disorders, with episodic anxiety associated with specific anxiety inducing situations less common than non-episodic anxiety. This high commonality of anxiety disorders highlights a pressing need for efficient identification and treatment of anxiety in patients with Parkinson’s disease.

WORST: Psychiatric disorders associated with increased dental decay

In 19 papers on depression and/or anxiety and seven on dental phobia/anxiety, covering a total of 334,503 subjects, all psychiatric diagnoses were associated with an increased likelihood of dental decay and tooth loss (OR=1.22).

The results underline the requirement for collaboration between dental and psychiatric practitioners to promote better oral health. The researchers propose possible interventions such as oral health assessments using standard checklists that can be completed by non-dental personnel, help with oral hygiene, management of medication-related dry mouth and early dental referral.

References

Bonde, J., Utzon-Frank, N., Bertelsen, M., Borritz, M., Eller, N., Nordentoft, M., Olesen, K., Rod, N., & Rugulies, R. (2016). Risk of depressive disorder following disasters and military deployment: systematic review with meta-analysis The British Journal of Psychiatry, 208 (4), 330-336 DOI: 10.1192/bjp.bp.114.157859

Bonfils, K., Lysaker, P., Minor, K., & Salyers, M. (2016). Affective empathy in schizophrenia: a meta-analysis Schizophrenia Research DOI: 10.1016/j.schres.2016.03.037

Broen, M., Narayen, N., Kuijf, M., Dissanayaka, N., & Leentjens, A. (2016). Prevalence of anxiety in Parkinson’s disease: A systematic review and meta-analysis Movement Disorders DOI: 10.1002/mds.26643

Dragan, M., & Hardt, J. (2016). Childhood adversities and risk for problematic alcohol use Addictive Behaviors, 59, 65-71 DOI: 10.1016/j.addbeh.2016.03.015

Gutermann, J., Schreiber, F., Matulis, S., Schwartzkopff, L., Deppe, J., & Steil, R. (2016). Psychological Treatments for Symptoms of Posttraumatic Stress Disorder in Children, Adolescents, and Young Adults: A Meta-Analysis Clinical Child and Family Psychology Review, 19 (2), 77-93 DOI: 10.1007/s10567-016-0202-5

Karyotaki, E., Smit, Y., Holdt Henningsen, K., Huibers, M., Robays, J., de Beurs, D., & Cuijpers, P. (2016). Combining pharmacotherapy and psychotherapy or monotherapy for major depression? A meta-analysis on the long-term effects Journal of Affective Disorders, 194, 144-152 DOI: 10.1016/j.jad.2016.01.036

Kedzior, K., Gierke, L., Gellersen, H., & Berlim, M. (2016). Cognitive functioning and deep transcranial magnetic stimulation (DTMS) in major psychiatric disorders: A systematic review Journal of Psychiatric Research, 75, 107-115 DOI: 10.1016/j.jpsychires.2015.12.019

Kisely, S., Sawyer, E., Siskind, D., & Lalloo, R. (2016). The oral health of people with anxiety and depressive disorders – a systematic review and meta-analysis Journal of Affective Disorders, 200, 119-132 DOI: 10.1016/j.jad.2016.04.040

Spijkerman, M., Pots, W., & Bohlmeijer, E. (2016). Effectiveness of online mindfulness-based interventions in improving mental health: A review and meta-analysis of randomised controlled trials Clinical Psychology Review, 45, 102-114 DOI: 10.1016/j.cpr.2016.03.009

Zhang, Y., & Han, B. (2016). Positive affect and mortality risk in older adults: A meta-analysis PsyCh Journal DOI: 10.1002/pchj.129

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