Table 2.
Summary of studies of olfactory identification in affective disorders.
| Study | Number of participants (f/m) and diagnosis | Mean age ± SD | Severity-scores | Odors and test method | Olfactory identification |
|---|---|---|---|---|---|
| Amsterdam et al., 1987 | C: 51 (34/17) | C: / | P: 18 – 37 (HAM-D) | UPSIT | P = C |
| P: 51 (34/17); MDD/BPD II | P: m: 49 ± 14 | ||||
| f: 43 ± 13 | |||||
| Clepce et al., 2010 | C: 37 (21/16) | C: / | / (BDI and SHAPS) | Sniffin' sticks | P < C (acute MDD) |
| P: 37 (21/16); MDD | P: m: 48.31 ± 11.95 | P = C (in remission) | |||
| f: 47.52 ± 11.33 | |||||
| Cumming et al., 2011 | C: 22 (11/11) | C: 35.5 ± 9.8 | P: 16.3 ± 9.5 (BPRS) | UPSIT | BPD < C |
| P: 20 (10/10); BPD | P: 34.6 ± 11.3 | 9.9 ± 8.0 (YMRS) | |||
| 12.0 ± 8.2 (HAM-D) | |||||
| Kopala et al., 1994 | C: 77 (47/30) | C: 32.5 ± 11.1 | / | UPSIT | P = C |
| P: 21 (13/8); MDD | P: 37.0 ± 9.6 | ||||
| Krüger et al., 2006 | BPD + ETE: 7 (1/6) | BPD + ETE: 33.9 ± 10.7 | BPD + ETE: 0.8 ± 1 (HAM-D) 0.8 ± 1.2 (SRMI) | Sniffin' sticks | BPD + ETE = BPD – ETE |
| BPD – ETE: 9 (5/4) | BPD – ETE: 46.1 ± 11.6 | BPD – ETE: 0.4 ± 0.7 (HAM-D) 1.4 ± 1 (SRMI) | |||
| Lombion-Pouthier et al., 2006 | C: 58 (36/22) | C: 38.4 ± 13.96 | P: 23.75 ± 5.74 (BDI) | Test olfactif | P = C |
| P: 49 (35/14); MDD | P: 43.4 ± 17.54 | ||||
| McCaffrey et al., 2000 | AD: 20 (13/7) | AD: 74.15 ± 7.86 | AD: 20.85 ± 5.22 (MMSE) | Pocket smell test | MDD > AD |
| MDD: 20 (11/9) | MDD: 67.55 ± 7.29 | MDD: 28.6 ± 1.54 (MMSE) | |||
| Naudin et al., 2012 | C: 54 (36/18) | C: 49.5 ± 12.5 | C: 2.33 ± 2.3 (MADRS) P (acute MDD): 35.1 ± 4.5 (MADRS) | Identification of odors (n = 8) from a list of four descriptors | P(acute MDD) = P(clinically improved) = C |
| P: 18 (12/16); MDD | P: 50.1 ± 13.3 | P (clinically improved): 9.1 ± 5.6 (MADRS) | |||
| Negoias et al., 2010 | C: 21 (15/6) | C: 39.62 ± 11.39 | P: 29.67 ± 10.84 (BDI) | Sniffin' sticks | P = C |
| P: 21 (17/4); MDD | P: 36.86 ± 10.13 | ||||
| Oren et al., 1995 | C: 21 (16/5) | C: 38 ± 9 | P: 29 ± 6 (HAM-D,SAD-Version) | UPSIT | P (SAD) = C |
| P: 21 (16/5); SAD | P: 38 ± 9 | ||||
| Pause et al., 2003 | C: 22 (14/8) | C: 48.4 ± 11.9 | C: 3.6 ± 3.2 (BDI); 2.6 ± 3.5 (HAM-D) | PEA, isobutyraldehyde, identification of odors from a set of three odors | P = C |
| P: 22 (14/8); MDD | P: 47.2 ± 10 | P: 25.7 ± 9.4 (BDI), 21.8 ±8.9 (HAM-D) | |||
| Pentzek et al., 2007 | C: 30 (24/6) | C: 77.07 ± 6.81 | C: 4.5 ± 3.34 (HAM-D), 8.83 ± 3.02 (ADAS-cog); | Sniffin' sticks | A < C |
| P: AD: 20 (15/5) | AD: 75.95 ± 9.09 | AD: 5.1 ± 4.72 (HAM-D), 25.05 ± 7.57 (ADAS-cog); | A < MDD | ||
| MDD 20 (15/5) | MDD: 73.45 ± 5.61 | MDD: 19.05 ± 7.57 (HAM-D), 9.4 ± 3.22 (ADAS-cog) | MDD = C | ||
| Postolache et al., 1999 | C: 24 (17/7) | C: 42.1 ± 11.8 | / | UPSIT | P = C |
| P: 24 (17/7); SAD | P: 42.8 ± 9.7 | ||||
| Serby et al., 1990, 1992 | C: 9 (/) | C: 50 – 59 | P: 19.9 ± 1.6 (HAM-D) | UPSIT; Yes/No task | UPSIT: P < C |
| P: 9 (0/9) MDD | P: 50 – 59 | Yes/No task: P = C | |||
| Solomon et al., 1998 | AD: 20 (12/8) | AD: 74.5 ± 7.77 | / | Pocket smell test | MDD > AD |
| MDD: 20 (13/7) | MDD: 69.4 ± 7.69 | ||||
| Swiecicki et al., 2009 | C: 30 (20/10) | C: 35.4 ± 2.1 | C: 0.5 ± 0.3 (HAM-D), 1.9 ± 0.5 (BDI) | Sniffin' sticks | RDD = BPD = C |
| P: 46 (RDD: 20, BPD: 21) | RDD: 35.7 ± 2.3 | RDD: 15.2 ± 1.6 (HAM-D), 27.2 ± 2.8 (BDI); | |||
| BPD: 39.6 ± 2.5 | BPD: 14.1 ± 1.0 (HAM-D), 23.2 ± 1.8 (BDI) | ||||
| Warner et al., 1990 | C: 8 | C: 32 (20 – 44) | / | UPSIT | P = C |
| P: 6; MDD | P: 37 (28 – 50) | ||||
| Zucco and Bollini, 2011 | C: 12 (6/6) | C: 39.8 ± 7.1 | / | Identification of odors (n = 10) from a list of four descriptors | Severe MDD < Mild MDD = C |
| P: 12 (6/6) Mild MDD; | P: Mild MDD: 41.3 ± 6.4 | ||||
| 12 (6/6) Severe MDD | Severe MDD: 41.9 ± 6.2 |
f, female; m, male; C, controls; P, patients; MDD, major depressive disorder; BPD II, bipolar disorder II; HAM-D, Hamilton Depression Rating-Scale; UPSIT, University of Pennsylvania Smell Identification Test; =, no difference between groups; P < C: patients performed worse than controls; P > C patients performed better than controls; BDI, Beck's Depression Inventory; SHAPS, Snaith-Hamilton-pleasure-scale; BPRS, Brief Psychiatric Rating Scale; YMRS, Young Mania Rating Scale; BPD + ETE, bipolar disorder with event triggered episodes; BPD – ETE, bipolar disorder without event triggered episodes; SRMI, Self-Report Manic Inventory; AD, Alzheimer's dementia; MMSE, Mini-Mental State Exam; PEA, Phenyl-ethylalcohol; MADRS, Montgomery-Asberg Depression Rating Scale; SAD, seasonal Affective Disorder;ADAS-cog, Alzheimer's disease Assessment Scale; RDD, unipolar recurrent depressive disorder; BPD, bipolar disorder; /, no information available.