Correlation of cigarette-induced increase in serum nicotine levels with arginine vasopressin concentrations in the syndrome of self-induced water intoxication and psychosis (SIWIP)

Development of diagnostic criteria and severity scale for polydipsia: A systematic literature review and well-experienced clinicians' consensus

Despite the clinical importance of polydipsia, no diagnostic criteria or severity scales that comprehensively assess this condition are available. Thus, we aimed to develop diagnostic criteria and a severity scale for polydipsia based on a systematic review and well-experienced clinicians' consensus. We performed a systematic review, identified 27 studies related to diagnostic criteria or severity classification for polydipsia, and extracted items used to assess polydipsia in these studies. Ten well-experienced clinicians-5 psychiatrists and 5 nurses-participated in the Delphi method. They evaluated 39 items extracted based on the results of the systematic review regarding (1) their necessity in diagnosing and assessing the severity of polydipsia, and (2) their relative importance rated on 7-point scale among the items included in the severity scale. The Polydipsia Diagnostic Criteria (PDC) included 4 essential items-excessive drinking, low serum sodium level or low serum osmolality, abnormal normalized diurnal weight gain, and low urine specific gravity-based on consensus reached using the Delphi method. The Polydipsia Severity Scale (PSS) included 13 items with a maximum score of 59. The first diagnostic criteria and symptom scale for polydipsia were developed based on the findings of a systematic review and well-experienced clinicians' consensus.

Brain circuit dysfunction in a distinct subset of chronic psychotic patients

OBJECTIVE

To identify the mechanism of unexplained hyponatremia and primary polydipsia in schizophrenia and its relationship to the underlying psychiatric illness.

METHODS

Briefly review previous studies that led to the conclusion the hyponatremia reflects altered hippocampal inhibition of peripheral neuroendocrine secretion. In greater detail, present the evidence supporting the hypothesis that circuit dysfunction associated with the hyponatremia and the polydipsia contributes to the underlying mental disorder.

RESULTS

Polydipsic patients with and without hyponatremia exhibit enhanced neuroendocrine responses to psychological stress in proportion to structural deformations on their anterior hippocampus, amygdala and anterior hypothalamus. Nonpolydipsic patients exhibit blunted responses and deformations on other hippocampal and amygdala surfaces. The deformations in polydipsic patients are also proportional to diminished peripheral oxytocin levels and impaired facial affect recognition that is reversed by intranasal oxytocin. The anterior hippocampus is at the hub of a circuit that modulates neuroendocrine and other responses to psychological stress and is implicated in schizophrenia. Preliminary data indicate that other measures of stress reactivity are also enhanced in polydipsics and that the functional connectivity of the hippocampus with the other structures in this circuitry differs in schizophrenia patients with and without polydipsia.

CONCLUSION

Polydipsia may identify a subset of schizophrenia patients whose enhanced stress reactivity contributes to their mental illness. Stress reactivity may be a symptom dimension of chronic psychosis that arises from circuit dysfunction that can be modeled in animals. Hence polydipsia could be a biomarker that helps to clarify the pathophysiology and heterogeneity of psychosis as well as identify novel therapies. Clinical investigators should consider obtaining indices of water balance, as these may help them unravel and more concisely interpret their findings. Basic researchers should assess if the polydipsic subset is a patient group particularly suitable to test hypotheses arising from their translational studies.

A systematic review of the ability of urine concentration to distinguish antipsychotic- from psychosis-induced hyponatremia

Life-threatening hyponatremia in psychotic patients is common and typically is attributable to either antipsychotic medication or to acute psychosis in those with the polydipsia-hyponatremia syndrome. The preferred treatment for one situation may worsen the hyponatremia if caused by the other situation. Hence it is critical to distinguish between these two possibilities. Case reports and series were identified through electronic databases. Fifty-four cases of hyponatremia without recognized causes in psychotic patients were divided into those with dilute (<plasma osmolality) or concentrated (>plasma osmolality) urine. The distribution of urine concentration and measures likely to be associated with psychotic illness and its treatment were compared in both groups. Naranjo׳s scale was utilized to determine the probability hyponatremia was drug-induced. Urine osmolality fit a bimodal distribution (intersection 219mOsm/kg) better than a unimodal distribution. 'Probable' drug-induced cases occurred 6.8 (95%CI=1.6-28.9) times more often in those with concentrated urine. Acute psychotic exacerbations occurred 4.5 (95%CI=0.4-54.1) times more often in those with dilute urine. These findings, as well as several other trends in the data, indicate that measures of urine concentration can help distinguish between antipsychotic-induced and psychosis-induced hyponatremia.

Effect of COMT Val108/158Met genotype on risk for polydipsia in chronic patients with schizophrenia

Polydipsia is a serious condition often seen among patients with schizophrenia (SCZ). The cause of polydipsia is unknown; hence, it is hard to treat or manage. Animal studies showed that the drinking behavior is regulated by central dopaminergic neurotransmission at the hypothalamus. Meanwhile, the existence of a genetic predisposition to polydipsia in patients with SCZ has been suggested. The purpose of this study was to assess whether a functional polymorphism, Val(108/158)Met in the gene for catechol-O-methyltransferase (COMT), is associated with susceptibility to polydipsia using a Japanese sample of SCZ. Our sample includes 330 chronic patients with SCZ (83 polydipsic patients and 247 non-polydipsic controls). The common COMT Val(108/158)Met polymorphism was genotyped, and the differences in genotype distribution and allele frequency between cases and controls were evaluated using the χ(2) test. A significant association between the COMT Val(108/158)Met polymorphism and polydipsia was found (genotype distribution: χ(2) = 13.0, df = 2, p = 0.001; allele frequency: χ(2) = 7.50, df = 1, p = 0.006). The high-COMT activity group (Val/Val) was more frequent among patients with polydipsia compared with the low-COMT activity group (Val/Met + Met/Met) [odds ratio (OR) = 2.46]. The association survived after controlling for other possible confounding factors, including gender, age, age of onset, current antipsychotic dose, and smoking status. Our results suggest that the COMT Val(108/158)Met genotype may confer susceptibility to polydipsia in SCZ. To our knowledge, this is the first association study between the COMT gene and polydipsia in SCZ. Further studies with larger sample sizes are warranted to confirm present findings.

Hierarchical linear modeling (HLM) of longitudinal brain structural and cognitive changes in alcohol-dependent individuals during sobriety

BACKGROUND

Hierarchical linear modeling (HLM) can reveal complex relationships between longitudinal outcome measures and their covariates under proper consideration of potentially unequal error variances. We demonstrate the application of HLM to the study of magnetic resonance imaging (MRI)-derived brain volume changes and cognitive changes in abstinent alcohol-dependent individuals as a function of smoking status, smoking severity, and drinking quantities.

METHODS

Twenty non-smoking recovering alcoholics (nsALC) and 30 age-matched smoking recovering alcoholics (sALC) underwent quantitative MRI and cognitive assessments at 1 week, 1 month, and 7 months of sobriety. Eight non-smoking light drinking controls were studied at baseline and 7 months later. Brain and ventricle volumes at each time point were quantified using MRI masks, while the boundary shift integral method measured volume changes between time points. Using HLM, we modeled volumetric and cognitive outcome measures as a function of cigarette and alcohol use variables.

RESULTS

Different hierarchical linear models with unique model structures are presented and discussed. The results show that smaller brain volumes at baseline predict faster brain volume gains, which were also related to greater smoking and drinking severities. Over 7 months of abstinence from alcohol, sALC compared to nsALC showed less improvements in visuospatial learning and memory despite larger brain volume gains and ventricular shrinkage.

CONCLUSIONS

Different and unique hierarchical linear models allow assessments of the complex relationships among outcome measures of longitudinal data sets. These HLM applications suggest that chronic cigarette smoking modulates the temporal dynamics of brain structural and cognitive changes in alcoholics during prolonged sobriety.

Nicotine replacement therapy-associated syndrome of inappropriate antidiuretic hormone

Nicotine has been documented to regulate the release of plasma arginine vasopressin (AVP). The literature is inconclusive about the effects of nicotine replacement therapy on AVP release, although cigarette smoking has been shown to increase the release of AVP. No clinical case reports have documented the possible association between nicotine replacement and hyponatremia through AVP release. We report a case of a 39-year-old man who experienced syndrome of inappropriate antidiuretic hormone while on nicotine patch therapy. We theorize that the constant serum concentration of nicotine levels provided through the patch may cause hyponatremia through the continuous stimulation of vasopressin.

Cigarette use, drinking and voiding in schizophrenic patients with polydipsia and hyponatremia

Pre-smoking versus post-smoking amounts of drinking and voiding were compared in ten state hospital patients with schizophrenia and polydipsia. Cigarette use was significantly correlated with total amount drunk but was not associated with increased drinking or decreased voiding immediately following smoking. These findings revealed no nicotine effects upon thirst drive or urinary output, but suggest that drinking and smoking represent associated repetitive behaviors.

Hyper- and hyponatremia among geropsychiatric inpatients

We report our experience treating 14 elderly psychiatric patients with altered sodium states. Hypernatremia occurs more commonly among elderly psychiatric patients than among their younger counterparts, and elderly hypernatremic psychiatric patients suffer most commonly from dementia. Dilutional hyponatremia is less common and less severe among elderly schizophrenic patients compared with younger patients with schizophrenia. Central nervous system changes induced by altered sodium states among elderly psychiatric patients are sufficiently similar whether hyper- or hyponatremia is present; therefore, the clinician must not wait for specific features to develop, but must quickly measure serum sodium concentration in elderly psychiatric patients with altered mental states. Treatment of hypernatremia involves rehydration with normal saline or hypotonic solutions, and treatment of dilutional hyponatremia largely involves fluid restriction.

Multiple manifestations of renovascular hypertension

We report a case of hyponatremia, polyuria-polydipsia, hypokalemia, nephrotic syndrome, and hypertension caused by unilateral renal ischemia, and the resolution after nephrectomy of the ischemic kidney. The renin-angiotensin-aldosterone axis seems to play an essential role in the pathogenesis of these features. Mechanisms by which angiotensin II, hypokalemia, and proteinuria can affect salt and water balances, and the role of angiotensin II as a cause of heavy proteinuria are discussed. Renovascular hypertension should be considered in the differential diagnosis of hyponatremia, hypokalemia, and polyuria-polydipsia.

The role of nicotine and nicotinic mechanisms in neuropsychiatric disease

Cigarette smoking, and by implication nicotine, may be involved as a negative or positive risk factor in some neuropsychiatric disorders and possibly as a treatment in others. Nicotine exposure may be a negative risk factor for the development of Parkinson's disease, but a positive risk factor for the development of tardive dyskinesia. For Alzheimer's disease and Tourette's syndrome, the role of nicotine exposure is equivocal, however, the role of nicotine as a possible therapeutic agent, alone or in combination, remains an intriguing question. For functional psychiatric disorders, the data are suggestive of a link between tobacco use and at least exacerbation of some disorders. While nicotine exposure is unlikely to be critical in the genesis of these disorders, it may complicate the pharmacological therapeutics and long-term prognosis. Further research is needed to examine the actual importance of tobacco use in behavioural disturbances. The relative importance of central nicotinic mechanisms in normal and disordered human cognition and movement is now beginning to be fully explored.

Vasopressin in chronic psychiatric patients with primary polydipsia

Twelve chronic in-patients with primary polydipsia were studied, during free drinking and after fasting, by concurrent measurements of plasma AVP, serum sodium and osmolality, and urine volume, AVP, osmolality, and creatinine. A majority of the patients showed inappropriately high levels of AVP: plasma AVP estimations demonstrated that seven had Type I SIADH and two had Type II SIADH. Urinary AVP estimations confirmed inappropriately raised AVP in seven of the subjects tested, and there was a significant agreement between the plasma and urine diagnoses. Although able to concentrate their urine in response to fluid deprivation, the patients showed a decreased renal sensitivity to AVP. Despite the mitigating effect of decreased renal sensitivity to AVP, the SIADH seen in these patients appears to contribute to the development of water intoxication caused by polydipsia.

Polydipsia in the chronically mentally ill: a review

Polydipsia, or excessive intake of water, is reviewed in the chronically mentally ill from a nursing perspective. The purpose of this article is to review research related to excessive water ingestion, the magnitude and types of problems that these patients experience, and the treatment interventions reported. Future research and practice should focus on understanding the patient's experience of polydipsia and how it relates to the patient's level of functioning, testing assessment tools, and determining appropriate interventions.

Abnormal diurnal weight gain among chronically psychotic patients contrasted with acutely psychotic patients and normals

We found diurnal weight gain to be abnormal among 28 institutionalized chronically psychotic patients. They were weighed daily for 15 days at 7 a.m. and 4 p.m. We normalized the diurnal weight gain (NDWG) as a percentage by subtracting the 7 a.m. weight from the 4 p.m. weight, multiplying the difference by 100, and then dividing the result by the 7 a.m. weight. NDWG was 2.8 +/- 1.3% for the 28 study patients, 0.631 +/- 0.405% for 16 acutely psychotic controls, and 0.511 +/- 0.351% for 29 normals. Ninety-three per cent of the study sample had NDWG values above the upper limit of normal. Sex, diagnosis, smoking, baseline weight, blood pressure, and pulse did not explain these observations. NDWG related (N = 28, r = 0.552, P = 0.002) to antipsychotic drug dose. The implications of our findings are discussed.

Failure of antipsychotic drug dose to explain abnormal diurnal weight gain among 129 chronically psychotic inpatients

1. The diurnal weight gain was found to be abnormal among 129 chronically psychotic inpatients. 2. The patients were weighed at 7 a.m. and 4 p.m. weekly for three weeks. We normalized the diurnal weight gain (NDWG) as a percentage by subtracting the 7 a.m. weight from the 4 p.m. weight, multiplying the difference by 100, and then dividing the result by the 7 a.m. weight. 3. NDWG was 2.2 +/- 1.5 percent for 87 male patients compared (p less than .0001) with .53 +/- .41 for 14 male controls. 4. NDWG was 1.8 +/- 1.0 percent for 42 female patients compared (p less than .0001) with .49 +/- .30 for 15 female controls. 5. Seventy percent of male and female patients had NDWG values greater than two standard deviations above the mean values of controls. 6. Differences in age, sex, morning weight, antipsychotic drugs, lithium, carbamazepine, phenytoin, blood pressure, and pulse did not explain these findings.

Diurnal weight gain as a predictor of serum sodium concentration in patients with psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome)

Ten male patients (mean age 37.3 +/- 6.4 years) with psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome) underwent measurement of weight, sitting and standing blood pressure, and serum sodium concentration at 7 a.m. and 4 p.m. weekly for 8 consecutive weeks. Blood pressure was higher in the afternoon than in the morning. The diurnal decrease in serum sodium (141.4 +/- 2.8 to 134.2 +/- 4.8 mEq/l) was associated with a diurnal increase in weight (78.4 +/- 9.7 to 80.0 +/- 10.3 kg). When the weight increase was normalized by dividing by 7 a.m. weight (NDWG), the following relationship evolved: diurnal serum sodium decrease = 3.060 + [201.728 x NDWG]. Therefore, NDWG accounted for 63.1% of the variability of serum sodium. Using the known relationship of plasma water, total body water, and total body weight, we calculated that antidiuresis (afternoon weight gain) accounted for 62.5% of afternoon hyponatremia. Thus, two separate methods of calculating the relationship between antidiuresis and hyponatremia provided remarkably similar findings. We derived a table to predict 4 p.m. serum sodium values based on 7 a.m. weight, 7 a.m. serum sodium, and 4 p.m. weight.

Diurnal variation in water homeostasis among schizophrenic patients subject to water intoxication

Among seven schizophrenic patients subject to water intoxication (six men and one woman, mean age 39.1 +/- 6.9 years), we measured serum sodium, plasma arginine vasopressin, and urine osmolality at 7 a.m. and 4 p.m. on eight consecutive Thursdays. On the days of greatest diurnal change in serum sodium, the 7 a.m. serum sodium was 141.1 +/- 1.8 mEq/l and the 4 p.m. value was 129.9 +/- 3.2 mEq/l. Plasma vasopressin also tended to be lower at 4 p.m. but, in many cases, was inadequately suppressed for the level of hyponatremia. The urine was dilute at both 7 a.m. and 4 p.m. and mean urine osmolality did not differ at the two times. In three patients, urine osmolality was consistently subnormal relative to plasma vasopressin at both 7 a.m. and 4 p.m. This abnormality was consistent with nephrogenic diabetes insipidus secondary to lithium and, possibly, phenytoin which the patients received to protect them against hyponatremia. We conclude that the combination of polydipsia and abnormal osmoregulation of vasopressin secretion contributes importantly to the afternoon hyponatremia found in schizophrenic patients subject to water intoxication.

The use of demeclocycline in the treatment of patients with psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome)

Eight patients (7 men and 1 woman, mean age 43.1 +/- 8.9 years) with psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome) underwent treatment with demeclocycline in an effort to normalize serum sodium levels and thereby protect the PIP patients against complications including hyponatremic seizures and coma. There tended to be an improvement (p = .080) in early morning serum sodium following treatment with demeclocycline (baseline 132.6 +/- SD 3.3 and treatment serum sodium 134.8 +/- SD 3.3 mEq/1). At the same time, there was an increase (p = .043) in urinary specific gravity following treatment with demeclocycline (baseline 1.0047 +/- SD .0029 and treatment urinary specific gravity 1.0063 +/- SD .0026). Clinical indications for and potential mechanisms of action of demeclocycline treatment in the PIP syndrome are discussed.

Abnormal diurnal weight gain among long-term patients with schizophrenic disorders

We found diurnal weight gain to be abnormal among 65 long-term patients with schizophrenic disorders. Patients were weighed at 7 a.m. and 4 p.m. serially and diurnal weight gain was normalized (NDWG) as a percentage by subtracting the 7 a.m. weight from the 4 p.m. weight, multiplying the difference by 100, and then dividing the result by the 7 a.m. weight. NDWG was 2.2 +/- 1.5% for 47 male patients compared (P = 0.001) with 0.6 +/- 0.4% for 11 male controls. NDWG was 1.7 +/- 0.7% for 18 female patients compared (P less than 0.0001) with 0.5 +/- 0.3% for 14 female controls. We hypothesize that NDWG may be an index of both the severity and duration of the schizophrenic disorder.