Table 1

Study characteristics

StudyParticipants and primary outcomeDesignDemographics of treatment groups (mean years, SD)Outcome
Depression and anxiety (individual CBT)
 Cole and Vaughan (2005)345 PD
Primary outcome: GDS
Individual CBT case series
Duration: 7 weeks; Follow-up: 8 weeks
Age 73.6±13.4
Disease duration 3.3±1.9
Improvement in mood symptoms in four of five patients post treatment but sustained effect at 1 month in two of five patients. Significant medical illness, lower baseline level of depressive symptoms and cognitive impairment were significant moderators of long-term gains. CBT was not associated with change to quality of life.
 Dobkin et al (2006)35Three PD and three carers
Primary outcome: HAM-D
Individual CBT and caregiver case series
Duration: not given; follow-up: 4 weeks
Age 62.7±12.2
Disease duration 5±4
Reduction in depressive symptoms during intervention and 1 month follow-up. There was also a decrease in negative thoughts and increase in perceived support. Minimal change to anxiety symptoms.
 Dobkin et al (2007)3015 PD and 15 carers
Primary outcome: HAM-D
Uncontrolled 10–14-week CBT plus educational programme for caregivers
Duration: 10–14 weeks; follow-up: 4 weeks
Age 64.2±9.6
Disease duration 5.1±3.2
Decrease in depression with 80% being treatment responders. There was also decrease in negative inferences, increased perception of social support but non-significant improvement in anxiety. Depression effect maintained at 4 months.
 Dobkin et al (2011)2580 PD
Primary outcome: HAM-D
Controlled CBT plus educational programme for caregivers (n=41) vs clinical monitoring (n=39)
Duration: 10–14 weeks; Follow-up: 4 weeks
Age 63.7±9.9
Disease duration 6.5±5.5
Significant reduction in depression scores; Improvement for anxiety (d=1.19), stress (d=1.10) social functioning, UPDRS ( week 10 and 14).
 Dreissig (1999)2679 PD
Primary outcome: PROGRESSOR 230
Controlled self-help and CBT (n=9) vs treatment at usual (n=70)
Duration: 12 weeks (6 sessions); Follow-up: none
Age 52.7±unknown
Disease duration 8.6±unknown
Improvement in anxiety and hopelessness levels.
 Farabaugh et al (2010)318 PD
Primary outcome: HAM-D
Uncontrolled CBT case series
Duration: 12 weeks; follow-up: none
Age 63.6±7.5
Disease duration unknown
57% remitted at study end (defined as HAM-D <7) with a significant reduction in HAM-D scores for the group. HAM-D related to frequency and degree of negative thoughts. There was no main effect of therapy on scales of perceived stress and automatic thoughts.
 Feeney et al (2005)324 PD
Primary outcomes: BDI and STAI-S
Uncontrolled CBT case series
Duration: 8 weeks; follow-up: 12 weeks
Age 65.3±11
Disease duration 4.8±4.9
3 of the 4 patients improved in terms of depression at 1 month follow-up and 2 of 4 at intervention end. No clinically significant improvement in anxiety scores.
 Shinmei et al (2015)3319 PD
Primary outcome: HAM-D
Uncontrolled CBT study
Duration: 6 weeks; follow-up: 12 weeks
Age 63.8±9.9
Disease duration 6.4±3.5
Significant improvement of depression at study end (HAM-D score, Hedges' g=−1.02) with the effects being maintained at 3-month follow-up.
 Troeung et al (2014)2918 PD
Primary outcome: DASS-21
Controlled CBT (n=11) vs waitlist (n=7)
Duration: 8 weeks; follow-up: 16 weeks
Age 68±7.7
Disease duration 5.7±5.5
Significant improvement in anxiety and depression scores post treatment. Improvement sustained at 6 months (Cohen's d=0.94 to d=2.26). No change to quality of life. Significant reduction in frequency of depressive (Cohen's d=1.26) and anxiety (Cohen's d=0.92) thoughts.
Depression and anxiety (distance CBT)
 Dobkin et al (2011)3621 PD
Primary outcome: HAM-D
Uncontrolled telephone CBT plus caregiver educational sessions
Duration: 10 weeks; follow-up: 4 weeks
Age 65.9±9.4
Disease duration 7.5±9.4
Significant improvement in depression with 62% meeting criteria for response at treatment end and 52% at 4-week follow-up. Gains in depression severity (BDI score), negative thoughts and coping. Treatment gains at 5-weeks post intervention start and maintained at 4-week follow-up. No significant effects on quality of life, problem-focused coping, sleep, social support or carer burden.
 Kraepelien et al (2015)389 PD
Primary outcome: HADS
Uncontrolled internet-based CBT
Duration: 12 weeks; follow-up: None
Age 66±11.6
Disease duration 8.1±3.9
Significant improvement in depression and anxiety scores (HADS). No significant change in MADRS-S, insomnia, quality of life or non-motor symptoms. Moderate degree of satisfaction with therapy.
 Veazey et al (2009)3710 PD
Primary outcomes: PHQ-9 and BAI
Controlled telephone CBT (n=5) vs support group (n=5)
Duration: 8 weeks; follow-up: 4 weeks
Age 66±9.9
Disease duration unknown
Improvement in anxiety and depression scores for groups vs baseline. Quality of life reduced in CBT group at 4-week follow-up.
Impulse control disorder
 Okai et al (2013)2745 PD
Primary outcomes: CGI, NPI and carer burden
Controlled face-to-face CBT (n=28) vs waitlist (n=17)
Duration: 12 weeks; follow-up: 12 weeks
Age 59.3±8.1
Disease duration 10.5±6.0
Significant improvement in CGI and NPI. 44% of treatment group did not meet ICD criteria at 12-week follow-up. No significant improvement in carer burden or distress. Improvement in work and social adjustment, anxiety and depression.
 Jimenez-Murcia et al (2012)4715 PD and 45 non-PD pathological gamblers
Primary outcomes: SOGS
Retrospective controlled CBT
Duration: 8 weeks; follow-up:
Age 62.7±8.5
Disease duration unknown
The authors found higher rate of relapse (25% vs 11%) and drop-out from therapy (29% vs 9%) for the PD relative non-PD pathological gamblers. However, this difference did not reach statistical significance.
Insomnia
 Rios Romenets et al (2013)2818 PD
Primary outcomes: SCOPA and ISI
Controlled face-to-face of group CBT plus light therapy (n=6) vs Doxepine 10 mg (n=6) vs placebo light therapy (n=6)
Duration: 6 weeks; follow-up: none
Age 64.5±16.3
Disease duration 5.2±1.8
Significant improvement in insomnia severity (ISI) but not SCOPA sleep score (doxepine was better than placebo for both). Examiner-rated but not participant-rated CGI improved. No change to daytime sleepiness, BDI, sleep hygiene, dysfunctional sleep beliefs or cognition. No improvement in depression scores with CBT.
 Yang and Petrini (2012)4925 PD
Primary outcomes: PDSS and sleep diary
Uncontrolled telephone and face-to-face CBT
Duration: 4 weeks; follow-up: 12 weeks
Age 65.2±unknown
Disease duration unknown
Improvement in PDSS and sleep diary measures (onset latency, wake after sleep onset, total sleep time, time in bed and sleep efficiency).
Carer distress
 A'Campo et al (2010)42151 PD and 137 carers
Primary outcome: BELA-A-K (carer psychosocial problems)
Group educational programme with CBT elements for patients and caregivers
Duration: 8 weeks; follow-up: none
Age 64.4±9.2
Disease duration 6.5±4.3
Patients: improvement in psychosocial burden and visual-analogue scale depression score but no improvement in quality of life or self-reported depression. Carers: improvement in psychosocial burden and visual-analogue scale mood scores but no change to health state and self-reported depression.
 Macht et al (2007)43151 PD
Primary outcome: Questionnaire on the acceptability of programme
Group educational programme with CBT elements for patients
Duration: 8 weeks; follow-up: none
Age 64.4±9.2
Disease duration unknown
67–80% felt intervention was appropriate and fulfilled expectations. Significant improvement in mood (visual-analogue scale) and psychosocial problems. No change to quality of life and self-rating depression score
 Secker and Brown (2005)4630 carers
Primary outcome: GHQ-28
Controlled study of session CBT (n=15) vs treatment as usual (n=15)
Duration: 12–14 weeks; follow-up: 12 weeks
Age 59.1±12.2
Disease duration: not applicable
Reduction of psychological distress (total GHQ-28 scores) for the treatment group at intervention end. The CBT group also had a decrease in somatic, anxiety, insomnia, social dysfunction but not depression GHQ-28 scores (as well as GDS scores). Effect was maintained at 12-week follow-up.
 Simons et al 20064422 PD and 14 carers
Primary outcome: BELA-A-K (Carer psychosocial problems)
Group educational programme with CBT elements for patients and caregivers
Duration: 8 weeks; follow-up: none
Age 65±7.3
Disease duration 7.6±5.0
Patients and carers approved of the programme and improved in terms of visual-analogue mood scores. No significant differences for carers’ quality of life, psychosocial problems, self-reported depression.
  • BAI, Beck Anxiety Inventory; BDI, Beck Depression Inventory; BELA-A-K, Belastungsfragenbogen Parkinson Angehörigen kurzversion; CGI, Clinical Global Impression; DASS-21, Depression, Anxiety and Stress Scale-21; GDS, Geriatric Depression Scale; GHQ-28, General Health Questionnaire—28 items; HADS, Hospital Anxiety and Depression scale; HAM-D, Hamilton Depression Scale; ISI, Insomnia Severity Index; MADRS-S, Montgomery Asberg Depression Rating Scale—Self rating version; NPI, Neuropsychiatric Inventory; PDSS, Parkinson's Disease Sleep Scale; PHQ-,9Patient Health Questionnaire-9; PROGRESSOR 230, The Psychological Profile Questionnaire; SCOPA-S, Scales for Outcomes in PD-Sleep; SOGS, South Oaks Gambling Screen; STAI-S, State subscale of State and Trait Anxiety Inventory.