Table 1.
Clinical measures and indices of water imbalance in patient groups
| Polydipsic | Nonpolydipsic | ||
|---|---|---|---|
| Hyponatremic (PHS) | Normonatremic (PNS) | Normonatremic (NNS) | |
| AM Plasma Osmolality, mmol/kg*(SD) | 279.4 (6.2) | 291.7 (4.5) | 289.5 (3.4) |
| PM Urine Osmolality, mmol/kg^ (SD) | 140 (154) | 258 (101) | 746 (368) |
| Age at onset, y (SD) | 23.8 (10.0) | 21.0 (4.3) | 20.6 (3.7) |
| PANSS Positive (SD) | 13.7 (5.7) | 16.4 (4.3) | 17.3 (7.5) |
| PANSS Negative (SD) | 18.4 (9.3) | 13.5 (4.2) | 13.8 (4.7) |
| PANSS General (SD) | 28.6 (11.1) | 27.0 (5.6) | 29.3 (10.3) |
| GAF (SD) | 35.8 (8.7) | 42.5 (7.2) | 41.1 (4.1) |
| Chlorpromazine Equiv., mgs/day@ (SD) | 482 (395) | 425 (259) | 532 (330) |
| Schizoaffective, No. (%) | 1 (14) | 1 (10) | 1 (11) |
| 2nd generation antipsychotic (%) | 3 (43) | 7 (70) | 3 (33) |
| Smoker (%)# | 4 (57) | 8 (80) | 3 (33) |
*
Group effect for plasma osmolality: P <.05; Post-hoc tests for hyponatremic polydipsic vs other two groups: each P<.05
^
Group effect for urine osmolality: P<.01; Post-hoc tests for nonpolydipsic normonatremic vs other two groups: each P < .01.
@
Three PHS, four PNS, and five NNS were receiving benztropine. Four patients PHS, four PNS, and one NNS received valproic acid.
#
There was a trend toward more smokers in the polydipsic normonatremic group than the other patient groups. No healthy controls were smokers.
All other group effects were not significant.
SD = Standard deviation